Finalist: Staff of The New York Times

A meticulous, controlling nature helped the Las Vegas gunman shield his plans from a close few. 

By Sabrina Tavernise, Serge F. Kovaleski and Julie Turkewitz

LAS VEGAS — Stephen Paddock was a contradiction: a gambler who took no chances. A man with houses everywhere who did not really live in any of them. Someone who liked the high life of casinos but drove a nondescript minivan and dressed casually, even sloppily, in flip-flops and sweatsuits. He did not use Facebook or Twitter, but spent the past 25 years staring at screens of video poker machines.

Mr. Paddock, a former postal worker and tax auditor, lived an intensely private, unsocial life that exploded into public view on Sunday, when he killed 58 people at a country music festival and then shot himself. But even with nationwide scrutiny on his life, the mystery of who he was has only seemed to deepen.

On Friday, a law enforcement official said Mr. Paddock’s girlfriend, Marilou Danley, told investigators that he seemed to be deteriorating in recent months both mentally and physically. Perhaps his methodical and systematic mind had turned in a lethal and unpredictable new direction. To the few people who knew him well, it is the only plausible explanation.

“I wish I could tell you he was a miserable bastard, that I hate him, that if I could have killed him myself I would have,” said Eric Paddock, a younger brother. “But I can’t say that. It’s not who he was. We need to find out what happened to him. Something happened to my brother.”

The Las Vegas police believe Mr. Paddock may have had a secret life. He had been buying guns since 1982. But something seemed to change last October. He went on a shopping spree, adding to his arsenal until late last month. One of his purchases, a shotgun, came from Dixie Gunworx in St. George, Utah. Chris Michel, the owner, said Mr. Paddock visited the store three times in January and February, making the 40-minute drive from Mesquite, Nev.

Mr. Michel recalled Mr. Paddock saying that he was stopping at a number of local gun dealers, that he had retired and moved to the area, and that he was trying to get back into his hobbies.

When it came to guns, Mr. Michel said, “he was not a novice.”

The son of a bank robber and a secretary, Mr. Paddock grew up lower middle class in Southern California in the 1960s. From an early age, he focused on gaining complete control over his life and not having to rely on anyone. He cycled through a series of jobs he thought would make him rich, Eric Paddock said.

“He went to work for the I.R.S. because he thought that’s where the money was, but it turned out the money wasn’t there,” the younger Mr. Paddock said. “He went to the aerospace industry but the money wasn’t there either. He went to real estate and that’s where the money was.”

Stephen Paddock began buying and refurbishing properties in economically depressed areas around Los Angeles, teaching himself how to put in plumbing and install air-conditioning. By the late 1980s, “we had cash flow,” said Eric Paddock, who added that he had given his life savings to his older brother to invest and eventually became a partner in his company, because “that’s the kind of guy he was. I knew he would succeed.”

“He helped make my mother and I affluent enough to be retired in comfort,” he said.

With success came a rigidity and uncompromising attitude, along with two failed marriages, both short and childless. Stephen Paddock started gambling. Some who met him described him as arrogant, with a strong sense of superiority. People in his life bent to his will, even his mother and brother. He went out of his way for no one.

“He acted like everybody worked for him and that he was above others,” said John Weinreich, 48, a former executive casino host at the Atlantis Casino Resort Spa in Reno, where he saw Mr. Paddock frequently from 2012 to 2014. When Mr. Paddock wanted food while he was gambling, he wanted it immediately and would order with more than one server if the meal did not arrive quickly enough.

Mr. Weinreich said he would get irritated and “uppity about it.”

Mr. Paddock was uncompromising but he was also smart.

“I would liken him to a chess player: very analytical and a numbers guy,” Mr. Weinreich said. “He seemed to be working at a higher level mentally than most people I run into in gambling.”

Mr. Paddock cherished his solitude, his brother said. In 2003, he got his pilot’s license after training in the Los Angeles area, eventually taking the extra step to get an instrument rating so that he could legally fly in cloudy conditions with limited visibility. He bought cookie-cutter houses in Texas and Nevada towns with small airports so that he could park his planes. He was utterly unremarkable.

“This guy paid on time every time and did not cause any problems at any time,” said Lt. Brian Parrish, the spokesman for the Police Department in Mesquite, Tex., where he rented a hangar for $285 a month from 2007 through 2009. He also stored planes at the small airport in Henderson, Nev., from 2002 to 2010, an airport spokesman said, though it is not clear he ever lived at the local addresses to which they had been registered.

Even in death, Mr. Paddock seemed to stay true to his ways. He remained in control, answerable to no one but himself. He was ensconced in a carpeted hotel suite. He was wearing gloves, as he often did to protect his sensitive skin. He shot himself before the police broke into his room. A piece of paper with numbers written on it lay on a table near his body.

“If Steve decided it was time for Steve to go, Steve got up and left,” Eric Paddock said. “He did what he wanted to do when he wanted to do it.”

The ‘Most Boring’ Son

Mr. Paddock was the oldest, and least angry, of four boys growing up in the 1950s, said another brother, Patrick Benjamin Paddock II, 60, an engineer in Tucson. Stephen Paddock was born in Iowa, the home state of their mother, Irene Hudson.

“My brother was the most boring one in the family,” Patrick Paddock said. “He was the least violent one in the family, over a 30-year history, so it’s like, who?”

Their father, Patrick Benjamin Paddock, also known as Benjamin Hoskins Paddock, was mostly absent, living a life of crime even before the boys were born. A 1969 newspaper story described him as a “glib, smooth talking ‘confidence man,’ who is egotistic and arrogant.”

His rap sheet was long and included writing bad checks, stealing cars and robbing banks. He was on the F.B.I.’s most wanted list. The agency described him as an avid bridge player, standing 6-foot-4 and weighing 245 pounds, who “has been diagnosed as being psychopathic, with possible suicidal tendencies.”

Stephen Paddock learned resourcefulness and self-reliance from an early age. In 1960, when he was 7, his father went to prison for a series of bank robberies and the family moved to Southern California.

The boys’ mother raised them alone on a secretary’s salary, the younger Patrick Paddock said. The brothers would fight over who would get the whole milk. Powdered milk, less tasty but cheaper, was the norm. Their mother never explained where their father was.

“She kept that secret from the family,” Patrick Paddock said.

Stephen Paddock graduated from John H. Francis Polytechnic Senior High School in the Sun Valley neighborhood of Los Angeles in 1971, according to a Los Angeles Unified School District official. Richard Alarcon, a former Los Angeles city councilman, who lived near the Paddocks, said their neighborhood was working class, with a Japanese community center and tidy ranch houses bought with money from the G.I. Bill.

Mr. Alarcon took a science class with Mr. Paddock and remembered him as smart but with “a kind of irreverence. He didn’t always stay between the lines.”

He recalled a competition to build a bridge of balsa wood, without staples or glue. Mr. Paddock cheated, he said, using glue and extra wood.

“Everybody could see that he had cheated, but he just sort of laughed it off,” Mr. Alarcon said. “He had that funny quirky smile on his face like he didn’t care. He wanted to have the strongest bridge and he didn’t care what it took.”

A Knack for Making Money

Mr. Paddock spent his 20s and 30s trying to escape the unpredictability of poverty. He worked nights at an airport while going to the California State University, Northridge, his brother Eric said, and then at jobs with the Internal Revenue Service and as an auditor of defense contracts. But it was real estate that ultimately lifted Mr. Paddock to financial freedom.

In 1987, he bought a 30-unit building at 1256 W. 29th Street in Los Angeles, near the University of Southern California, according to property records. His brother Eric Paddock said the buildings they bought were not “Taj Mahals, but they were nice safe places.”

Crucially, they were excellent investments: Stephen Paddock more than doubled his money on his California holdings, which included at least six multifamily residences, according to property records. He made money in Texas, too. In 2012, he sold a 110-unit building in Mesquite, outside Dallas, for $8.3 million.

He was a good landlord. He kept the rents low, responded promptly to his tenants’ complaints, learned all their names and made sure they were happy. When one reliable tenant complained about a rent increase, he took half off the difference. He designed the ownership structure so his family would profit and installed his mother in a tidy house just behind the apartment complex in Mesquite, Tex.

Mr. Paddock had an apartment in the complex, but he mostly lived elsewhere. He had been married twice, but the apartment looked like a bachelor pad, said Todd Franks, a real estate broker in Dallas. “What you would expect from a 25-year-old single guy.”

To Mr. Franks, Mr. Paddock stood out because it was unusual for the landlord of a property that size to pay such close attention to the day-to-day running of his complex.

“He was frustrated by people who did stupid things,” Mr. Franks said.

He was also willing to fight to defend what was his. During the riots in Los Angeles in the 1990s, he went to the roof of an apartment complex he owned in a flak jacket and armed with a gun, waiting for the rioters, Mr. Franks said.

Though Mr. Paddock might have adopted an accommodating attitude toward his tenants and dressed casually — Mr. Franks remembered him regularly wearing sandals and a sweatsuit — Mr. Paddock was focused and astute when he made deals.

“He was a tough negotiator,” Mr. Franks said. “He wanted his price. His terms. He was a very savvy businessman.”

The House Advantage

By the 2000s, with both of his marriages long over, casinos became Mr. Paddock’s habitat. He liked being waited on, seeing shows and eating good food.

“He likes it when people go, ‘Oh, Mr. Paddock, can I get you a big bowl of the best shrimp anybody had ever eaten on the planet and a big glass of our best port?” Eric Paddock said.

Gambling made him feel important, if not social.

“You could tell that being in that high-limit gambling environment would lift him up,’’ said Mr. Weinreich, the Atlantis casino host in Reno. “He liked everyone doting on him.”

He sometimes called for company, inviting his brother Eric and his children for a free weekend in a luxury suite. But mostly he stayed alone.

A couple of years ago, Mr. Paddock stayed in one Las Vegas hotel gambling for four months straight, said a gaming industry analyst here who was briefed on Mr. Paddock’s gambling history.

The analyst described him as a midlevel high roller, capable of losing $100,000 in one session, which could extend over several days. He said Mr. Paddock may have lost that amount at the Red Rock Casino in Las Vegas within the last few months.

Playing a slot machine can be mindless and is usually a guaranteed win for the casino. That is not what Mr. Paddock played. His game, video poker, requires some skill. Players have to know the history of a particular machine. They can do that by reading a pay table, which tells them what each possible winning hand pays out.

One of the ways that video poker players get an advantage is to play casino promotions, which essentially pay out bonuses to winners, said Richard Munchkin, author of “Gambling Wizards: Conversations With the World’s Greatest Gamblers.” A gambler like Mr. Paddock will often “lock” a machine, meaning he or she monopolizes it and makes sure no one else uses it during a gambling session.

For one casino promotion, Mr. Paddock showed up two hours early, locked two machines and played them for 14 hours straight, Mr. Munchkin said, based on information he had compiled from other gamblers who were there at the time. The promotion lasted 12 hours, he said, “but he wanted to play for two hours before anybody got those machines. He knew they were the best machines based on pay tables.”

Mr. Paddock “knew the house advantage down to a tenth of a percent,” he said.

As for the mystery of why Mr. Paddock would go on a shooting rampage at the Mandalay Bay Resort and Casino and then kill himself, most in the gambling industry do not believe it had anything to do with money.

He was in good standing with MGM Properties, the owner of the Mandalay and the Bellagio, according to a person familiar with his gambling history. He had a $100,000 credit limit, the person said, but never used the full amount.

The Absent Neighbor

Mr. Paddock spent so much time in casinos that he was mostly a ghost in the neighborhoods where he had homes.

Colleen Maas, a neighbor of Mr. Paddock’s in Reno, said she had not seen him once in a year and a half, despite walking her dog three times a day and going to line dancing events with his girlfriend, Ms. Danley, at the community center.

He did travel. On his 60th birthday, April 9, 2013, he flew to the Philippines on Japan Airlines and stayed for five days, according to a spokeswoman for the Philippine Bureau of Immigration. The family of Ms. Danley, his girlfriend, lived there and she was visiting the country at the time. The couple went again for his birthday the following year.

When he did appear at his Reno home, he could be curt. Another neighbor, John McKay, recalled a day when he was hanging Christmas lights on a railing in his front yard when Mr. Paddock walked by. Mr. McKay said hello and yelled out, “Merry Christmas!” Mr. Paddock kept walking. “He said nothing,” Mr. McKay said. “Not a word. No eye contact.”

Even more baffling, when Mr. McKay tried to strike up a conversation with Mr. Paddock about Donald Trump during the election campaign, he got no response.

“Almost everyone has a reaction to Trump,” said Mr. McKay’s wife, Darlene.

Ms. McKay said that she would usually get up early each morning to watch the sunrise and, when Mr. Paddock was at his home, she would see him dressed in his gym clothes walking to the community center for a workout. Ms. McKay recalled something peculiar: “He always walked across the street and would never pass in front of our house.”

Mr. McKay said that he rarely saw a window or a door open at the house. One day he saw Mr. Paddock’s garage door open, and noticed a large safe inside.

It is not clear what set Mr. Paddock on his path to destruction. As early as 2010, he could no longer fly his planes. His medical certificate expired, according to Federal Aviation Administration records, and there are no indications that he renewed it.

Mr. Paddock bought his last house in Mesquite, Nev., a retirement community of 18,000 people about 90 minutes from Las Vegas that attracts golfers and gamblers from around the country. He seems to have paid in cash, according to property records, and, as he did with other houses, spent very little time there.

His neighbors added personal touches to their yards — decorative pots, plants of all colors and sizes. Mr. Paddock’s house was unadorned. One of the few things neighbors remembered about him was the solid-panel fence he erected. The message was clear: Mr. Paddock was a man who did not want to be seen. On Thursday, investigators had left. A tiny paint-splattered easel, its brush drawer open and empty, stood in the back yard.

Ms. Danley worked in Mesquite. She took a job booking sports bets at a local casino called the Virgin River, where gamblers sat together in rows watching horse races and waitresses circled in tight black skirts.

Several days a week, she attended morning mass at a local Catholic church, said Leo McGinty, 80, a fellow parishioner who knew her from the casino.

Ms. Danley dressed smartly and modestly, he said. She usually sat alone.

Reporting was contributed by Stephanie Saul, Vivian Yee and Susan Beachy from New York; Adam Goldman from Washington; Kitty Bennett from St. Petersburg, Fla.; Miriam Jordan from Los Angeles; Sheryl Kornman from Tucson; and Richard C. Paddock from Manila.

By Dave Philipps

Facing prison for a string of bank robberies, Benjamin Hoskins Paddock beamed cheerfully at a psychiatrist evaluating his fitness to stand trial, and mused at length — at times with “becoming modesty” — about his life stealing cars, running cons, enduring solitary confinement and getting fired from a job as a bus driver after playing tag with the buses.

“I’m a third time loser,” Mr. Paddock, the father of the Las Vegas gunman, Stephen Paddock, told the doctor with a smile, according to a summary of the doctor’s evaluation. Though he was in a jail cell in Phoenix, Mr. Paddock expressed no regrets, and claimed to have a genius IQ.

“Maybe,” he wondered aloud, “I’m an alert psychotic.”

A few years later he ended up on the F.B.I.’s most wanted list.

Nearly two weeks after the shooting in Las Vegas, investigators have found few clues to explain why Stephen Paddock amassed an arsenal of assault-style weapons and turned them on concertgoers at a country music festival. F.B.I. profilers are trying to construct a psychological makeup of Mr. Paddock, which probably includes the family history of mental illness.

If so, one of the most telling documents might be a yellowed, four-page psychiatric evaluation from 1960 that details the father who raised Stephen Paddock until he was 7 and who loomed over the family even after he disappeared.

When Benjamin Paddock sat for the examination, he was built like a refrigerator and wore a neatly trimmed blond mustache and horn-rimmed glasses that framed strikingly light gray eyes. Pleasant, clean-cut and “incongruously cheerful,” he chain smoked through the interview, offering a gripping biography with a “fluent command of language.”

“He smiles frequently, sometimes winningly, shows occasionally just a touch of ruefulness,” the psychiatrist, William B. McGrath, noted. “No despair, alarm or concern about his fate is manifest.”

“I get the impression he enjoys being an interesting subject of examination,” the doctor wrote. He concluded that Mr. Paddock was bright, with no history of “mental defect,” and was able to stand trial. But, the doctor added, Mr. Paddock had a “sociopathic personality.”

The portrait of Stephen Paddock that investigators have assembled stands in stark contrast: Reserved, even boring, he was an accountant and investor who liked to gamble only after calculating all the risks. Before the shooting, the authorities say, he had never broken the law. Among the many questions that are unanswered is what influence, if any, his father’s absence and infamy had on his life.

“We are establishing the timeline of the suspect’s life, his motivation and everybody else associated with him throughout time,” Sheriff Joseph Lombardo of the Las Vegas Metropolitan Police Department said. The F.B.I. has hundreds of agents on the case and more than 1,000 pieces of evidence, said Aaron Rouse, the special agent in charge in Las Vegas.

A statement from the Clark County coroner’s office said that an autopsy on Mr. Paddock had been completed, and that “multiple forensic analyses” would be performed, including an examination of brain tissue.

Benjamin Paddock had boasted during his psychological evaluation that his run-ins with authority started early and rarely stopped. He was an only child, pampered by his mother and not disciplined by his father. “I got away with an awful lot,” he told his evaluator. “I went where I felt like it, disrupting everybody’s schedule.” By 12 he was driving his own car.

He quit high school almost as soon as he started, then joined the Navy at age 15, but was discharged a few months later, he said, when the Navy figured out, “I wasn’t going to do what they wanted me to.”

He drove buses in Los Angeles, but got fired for a game of bus tag with other drivers.

In 1946 he was caught stealing a car in Chicago and reselling it in “a fraudulent fashion.” He spent five years in prison, 70 percent of it, he said, “in the hole,” or solitary confinement, because he was “unable or unwilling to abide by rules.”

When he got out, he made good money selling used cars in Chicago, but quit because, he explained, “the thrill had gone out of it.”

During that time he got married and fathered Stephen, who was born in 1953. He also set up a fraud ring that he said passed $90,000 in bad checks. He was caught and sent back to prison.

When he was released in 1956, he moved with his wife and son to Tucson. The couple had three more sons, and Benjamin Paddock operated a service station, a nightclub and a garbage disposal franchise. He bought a house and car, and got involved in the local hot rod and ham radio clubs.

He also walked into the sheriff’s office and offered to counsel troubled youths.

“I only took the incorrigibles,” he told his evaluator. “I have a knack for social work with kids. I told them I had a degree in social psychology and nobody bothered to check up on it. They regarded me as a leading light on juvenile delinquency.”

He boasted that none of his charges had ever ended up back in court.

While Stephen Paddock was playing at the family’s white ranch house, his father was robbing banks with a snub-nosed revolver and getting away in the family station wagon. He said the ham radio equipment he kept in the car was ideal for a robber because he could listen in on the police.

Benjamin Paddock was caught in 1960. But the bank robbery charges, he insisted to the psychiatrist, were a case of mistaken identity. A criminal syndicate was forcing him to take the rap.

For years after Mr. Paddock was arrested, his sons were told he was dead. Later they learned the truth and some visited him, his son Eric Paddock said, but none seemed to form a close relationship. Eric Paddock cursed his father in an interview and said he was angry at him for being more interested in crime than his family.

The authorities have not said what they know about the convict’s relationship with Stephen Paddock.

Facing trial, Benjamin Paddock insisted that he was not crazy. He said he had “never been mental ill, ‘Never even unconscious.’ ” As an aside, he explained that he could get a cushy job in the penitentiary that would beat the boredom of the mental hospital.

In the long account of his life, Mr. Paddock never expressed remorse. A few months later, a judge sentenced him to 20 years in a federal prison. He broke out after eight and spent much of the rest of his life on the lam.

Adam Goldman, Stephanie Saul and Sheri Fink contributed reporting, and Kitty Bennett contributed research.

By Sheri Fink

In the days after the shootings at the Route 91 Harvest festival in Las Vegas, many stories emerged of bystander courage. Volunteers combed the grounds for survivors and carried out the injured. Strangers used belts as makeshift tourniquets to stanch bleeding, and then others sped the wounded to hospitals in the back seats of cars and the beds of pickup trucks.

These rescue efforts took place before the county’s emergency medical crews, waylaid by fleeing concertgoers, reached the grassy field, an estimated half-hour or more after the shooting began. When they did arrive, the local fire chief said in an interview, only the dead remained.

“Everybody was treating patients and trying to get there,” Chief Gregory Cassell of the Clark County Fire Department, said of his personnel. “They just couldn’t.”

The experiences in Las Vegas have implications for the nation. Emergency medical services have changed how they respond to mass attacks, charging into insecure areas and immediately helping the injured rather than standing back. Still, every minute counts, and bystanders can play a critical role in saving lives, as shown in the aftermath to the shooting on Oct. 1 outside the Mandalay Bay Resort and Casino.

“The city functioned as a trauma center,” said Dr. Sean Dort, a surgeon at Dignity Health-St. Rose Dominican Hospital’s Siena campus in nearby Henderson, Nev. “What really makes this unique is the volume.”

What the Las Vegas shooting showed, trauma experts said, is that nascent efforts to teach and encourage the public to help the wounded in mass casualty emergencies should be expanded.

“Time is the most critical factor,” said Dr. Eric Goralnick, medical director of emergency preparedness at Brigham and Women’s Hospital in Boston, one of several trauma centers that were much closer to the Boston Marathon bombings in 2013 than the closest hospitals happened to be in Las Vegas. “People would talk about the golden hour. Really, what we’re talking about is the golden minutes.”

Several national programs have been started to train more people to stop bleeding, to add to those who pick up knowledge in the military or in scouting programs and the like. But Dr. Goralnick and others are still exploring the most effective and lasting ways to turn people without medical backgrounds into capable responders. Researchers are finding that people may need prompting or training to use tourniquets effectively, even when instructional materials are present with them.

“My observation is that the civilian sector is where the military was in this topic area in the early 2000s,” said Dr. Todd Rasmussen, an Air Force colonel and associate dean at the Uniformed Services University of Health Sciences in Bethesda, Md., which maintains a website with information on how to stop bleeding.

Roughly half of the 58 victims killed in the Las Vegas mass shooting died before reaching a hospital, based on mortality counts released by local medical centers. In the Iraq and Afghanistan wars, there were also many pre-hospital fatalities. “It’s convenient to put many of these deaths in the damn-shame category — ‘Well, we couldn’t have done anything anyway,’ ” Dr. Rasmussen said. While that reaction is understandable, he said, it was important to study what really caused the deaths, and whether any of the injuries might have been survivable.

In studying autopsies of service members killed in the early 2000s, Dr. Rasmussen and his colleagues found that many had life-ending wounds that could not be fixed. But some had wounds that could have been successfully repaired by surgeons if the patient had not already lost so much blood, he said.

Because of that finding, the military began training regular service members to stop bleeding, equipping them with individual first aid kits, which contain optimized tourniquets and wound dressings. Researchers have shown that lives have been saved as a consequence.

“We think the American public can, if they can use some of these same techniques, save lives in the same way nonmedical soldiers can save lives,” said Dr. Craig Goolsby, deputy director of the National Center for Disaster Medicine & Public Health at the Uniformed Services University.

The impression in Las Vegas is that they did just that. “Some of our patients were saved by bystanders,” said Dr. Deborah A. Kuhls, a professor of surgery at the University of Nevada, Las Vegas School of Medicine and the medical director of the trauma intensive care unit at University Medical Center of Southern Nevada. “One had put a belt on his thigh, and it probably saved his life. There was a lot of bleeding on the scene.”

In Las Vegas, several factors impeded the arrival of emergency medical workers at the scene of the shooting itself.

Confusion abounded. One fire crew that happened to be passing by during the first few minutes saw people running from the festival and heard what sounded like gunfire. “You got reports of anything?” a member of the fire crew, Capt. Ken O’Shaughnessy of Engine 11, asked a dispatcher over the radio. “That’s a negative, sir,” he was told. Three minutes later, the dispatcher confirmed that there was an active call.

Members of that crew remained nearby, and later assisted injured concertgoers.

“From what it sounds like talking to them, they didn’t identify the hot zone because they didn’t know where it was,” said Mr. Cassell, the fire chief. “They just knew they had dozens and dozens of critical patients.”

More than 10 minutes after the shooting began, a battalion chief advised firefighters to “stage at a distance” and put on protective vests and helmets as he tried to understand the situation and make contact with a police lieutenant on the scene. The battalion chief radioed in seven minutes later that there were reports of gunfire at both the concert grounds and the Mandalay Bay across the street. “We can’t approach it yet,” he said.

The injured were already fleeing and being carried out in several directions. “Those crews making their way to the concert venue were met at every turn by patients in the streets,” Mr. Cassell said. The fire department helped establish several assembly points, and ultimately, about 160 firefighters and emergency medical workers from departments in the region went to the scene.

Inside the nearly empty concert grounds after the shooting stopped, some volunteers remained, roaming among the fallen near the stage, checking pulses and finding some of them unconscious but still breathing.

“E.M.T.s, any E.M.T.s?” one man shouted to no avail as he recorded video. Then the lights cut out, and everything fell into darkness.

In another video posted by The Las Vegas Review-Journal, an injured man could be heard immediately after the shooting asking where the ambulances were. “They’re not going to come this way,” a policeman on a part of Las Vegas Boulevard north of the hotel and the concert site said to Raymond Page, a Clark County employee who was assisting the injured man. “Take him east,” the officer said. A few feet away, another police officer helped adjust the injured man’s tourniquet.

Over time, calls to 911 from other hotels where the injured had fled and taken shelter created the impression that shootings might be occurring in multiple locations. That “took away additional resources that were coming in,” Mr. Cassell said. Ultimately, he said, there were 60 reports from hotels that had to be checked.

Tactical rescue teams of police and firefighters assembled, put on the protective gear their departments had recently bought with the help of federal grants, and entered the hotels to bring out the victims as they were trained to do, based on lessons from mass shootings at Columbine High School and in Aurora, Colo. Capt. Joe Geeb of Clark County Engine Company 33 was assigned to the Tropicana Hotel, where there were several lightly wounded patients. He said in an interview that he was using his bulletproof vest and helmet for the first time on a real call.

By the time fire crews made it inside the concert grounds, they found only bodies. “Everybody that was alive or salvageable was dragged outside the venue by bystanders, all the great Samaritans,” Mr. Cassell said.

Those aiding the injured included off-duty firefighters, military medics, and nurses who happened to be attending the concert. Also assisting was Community Ambulance, a private company hired for the event whose 16 emergency medical technicians and paramedics had expected to treat concertgoers for sun exposure and intoxication.

Ultimately, fire department and private ambulances transported 200 patients to hospitals, according to estimates by fire officials. That means that the majority of the injured reached hospitals in private cars, pickup trucks and taxicabs, including patients who were put in those vehicles by firefighters, Mr. Cassell said. Representatives of 11 area hospitals said in interviews that they treated a total of 595 patients, although some may have been counted twice if they were transferred between hospitals.

Early reports suggest that luck played a role in ensuring that nearly all patients did not arrive at a single hospital, as happened at the Orlando Regional Medical Center after the 2016 mass shooting at the Pulse nightclub a few blocks away. On mobile phones, different mapping applications listed different hospitals in Las Vegas as the quickest to reach.

Sunrise Hospital and Medical Center, just under five miles from Las Vegas Village, reported treating 200 patients. Two other hospitals, University Medical Center and Desert Springs, each saw more than 100. Desert Springs is not a trauma center.

Even when emergency medical workers were on the scene, civilians continued to assist. “We had people who were shot holding pressure on other people’s wounds,” said Amber Ratto, a paramedic with American Medical Response and MedicWest, which sent about 120 vehicles and 250 staff members in response to the shooting.

Malachy Browne and Dave Philipps contributed reporting.

By John Branch

NOVATO, Calif. — I was on the sideline of a soccer field two Saturdays ago, watching my 12-year-old daughter and her Novato teammates. I don’t remember much about that game, but Novato won, and one of the goals was scored by the smallest girl on the team, a quick and feisty forward who wears a long ponytail and jersey No. 8. We whooped and cheered her name. I found out later that her parents weren’t there that afternoon. They were in Las Vegas for a getaway weekend.

About 36 hours later, I was on my way to Las Vegas myself, rushing to join my New York Times colleagues to cover the latest mass shooting, maybe bigger than them all. I hadn’t covered one of them since 1999, when I was in the wrong place at the right time and rushed into the aftermath of Columbine.

A colleague of mine and I checked into a massive suite at Mandalay Bay Resort and Casino, 11 floors directly below that of the shooter. It had the same view of the concert ground across the Strip, where investigators in the daylight were picking through the carnage of the night before. That was about when my wife sent me a text. That little soccer player’s mom was at the concert the night before, she said. She’s missing.

But Stacee Etcheber was not my story. The gunman was. I spent a week mostly about 100 feet below where the shooter committed mass murder, trying to solve the mystery of what he’d done. I talked to people, followed every lead and wrote stories. It’s what reporters do. It was a news story, as horrific as they come, and we’re trained to keep our emotional distance from the things that we cover.

Late that night, I stood in front of the window, the same one that a madman broke 11 floors above and used as a perch to shoot hundreds of people he did not know. The body count was on its way to 58. I thought about home.

Stacee’s family soon announced that she died. My wife and I didn’t really know Stacee much — obviously not well enough to notice that she was not among the few dozen people at a rec-level girls’ soccer game. But some of our closest friends were dear friends of hers, and our town is small enough that there was probably no more than two degrees of separation to the family.

My family was among the hundreds of people, friends and strangers, who crowded onto the grounds of an elementary school and held candles aloft during the vigil. My daughter was one of the dozens of kids who solemnly held roses in her honor, and she hugged her classmate and teammate when it ended. She and a couple of friends made a cake and delivered it to the Etchebers’ house the next day.

Orange was Stacee’s favorite color, and on Friday, after people bought as much orange ribbon as they could find at all the local craft stores, an army tied ribbons all around town, from the trees on downtown’s Grant Avenue to the posts in front of Pioneer Park. My wife and her friends tied them around the trees in front of the middle school where Stacee’s daughter goes to school, along with mine.

I missed it all. I was as close to the site of the shooting as you could get, and yet felt fully disconnected from the effect of the tragedy. One night I walked to the memorial that sprang up in the median of South Las Vegas Boulevard, the kind of now-familiar post-shooting memorial that I saw at Columbine almost two decades before, with balloons and flowers and candles. I found a photo of Stacee that had been placed in the middle of it all, and took a picture and sent it home.

In Las Vegas, Stacee was just one in a crowd, part of a list. But she and her family were all anyone talked or thought about back in Novato, and that is where I got my news. I heard that Stacee’s husband, a San Francisco police officer, was running with Stacee through the barrage of gunfire when he stopped to help someone; he told his wife to go on and never saw her alive again. I heard that television news trucks were parked in front of the house. I heard stories of friends pulling over in their cars to cry at the weight and nearness of it all. There were beautiful and crushingly sad Facebook posts in Stacee’s honor, the kind you see after every tragedy, except these were written by people I knew well.

I heard my wife, who grew up in a nearby town, tell me that she had never been more proud to call Novato home.

I checked out of that Mandalay Bay suite on Saturday morning, excused from reporting duties, and flew home in the hopes of making my daughter’s soccer game. I found the red rose from the vigil, starting to fade and wilt, in a vase on the kitchen counter. When we got to the game, we and the other parents were somewhat surprised to see Stacee’s husband and extended family there, too. Warming up with the girls was No. 8, with her long ponytail.

We all wore orange ribbons, attached by safety pins, including the girls on both teams. The Novato team wore orange armbands with the initials “S.E.” Before kickoff, both squads came across the field to the spectator side and lined up in straight lines. Our team’s coach asked the parents to stand for 30 seconds of silence. And then two of the league’s better teams played a rather meaningless soccer game, only this one felt about as meaningful as anything I’ve ever watched.

And it was late in the second half when the ball suddenly swung from one end to the other, and Stacee’s daughter gave chase through three retreating opponents and beat them all to the ball. And in one blink-and-you-missed-it moment, she booted the ball into the corner of the net for what held on as the winning goal.

Her teammates chased her and swarmed her, and they and she looked as free and happy as girls can be on a sunny fall Saturday afternoon with their friends. The parents jumped and cheered as loudly as I’ve heard parents cheer at a kids’ soccer game. Behind my sunglasses, I was bawling. It was the first time I’d cried all week.