Finalist: The Boston Globe, by John Tlumacki and David L. Ryan

The force of the first bomb blast near the finish line of the Boston Marathon knocks 78-year-old runner Bill Iffrig to the ground. As the second bomb explodes, Boston Police Officers Rachel McGuire, Kevin McGill and Javier Pagan react in the initial confusion. (Photo by John Tlumacki, April 19, 2013)

As police rush to the scene of the first blast near the finish line of the Boston Marathon, a second bomb explodes several blocks away. The shock wave from the first blast keeps the flags aloft lining the finish line. Behind the metal barricades, hundreds of people are injured and dozens fight for their lives. (Photo by David L. Ryan, April 19, 2013)

One of the heroes of the marathon bombings, Carlos Arredondo, scales over the barricades and starts breaking them down so first responders can get to the victims. (Photo by John Tlumacki, April 19, 2013)

Nicole Gross sits stunned on the Boylston Street sidewalk as Kevin Corcoran uses his belt as a tourniquet in an attempt to stem the bleeding of his wife Celeste's mangled legs. (Photo by John Tlumacki, December 15, 2013)

Eric Whalley is rushed from the scene by medical personnel. Quick action by first responders was credited with saving numerous lives. The medical team at the finish line, normally there to treat blisters and dehydration, assisted the critically injured within minutes of the blast. (Photo by David L. Ryan, April 16, 2013)

A woman kneels and prays near the scene of the first bombing on Boylston Street. Three people died and at least 260 were injured. (Photo by John Tlumacki, April 16, 2013)

Matt Smith and Zack Mione use t-shirts and apply pressure to help save Sydney Corcoran, 17, on the sidewalk at the site of the first bomb. A piece of shrapnel the size of a cell phone severed her femoral artery, and she nearly bled to death. (Photo by John Tlumacki, April 16, 2013)

First responders rush Victoria McGrath and Mery Daniel (at right) from the scene, as Krystara Brassard runs after her injured friend. Daniel suffered serious injuries resulting in the amputation of her left leg. (Photo by David L. Ryan, April 16, 2013)

Joe Duncan comforts Sydney Corcoran at the site of the first bomb. She was standing with her parents Celeste and Kevin to cheer on her aunt, who was running in the race. She fell fifteen feet away from her mother, who lost both of her legs in the bombing. (Photo by John Tlumacki, April 16, 2013)