On April 15, 2013, AP photographer Charlie Krupa captured some of the most iconic images of the Boston Marathon bombing. He was working in the press room when he heard the first explosion and then the second, and that’s when he realized something very wrong had happened and whatever that something was, he had to photograph it. So Charlie instantly grabbed his camera and bolted for the door to get himself outside to see what was happening. Through all the commotion he began pointing his camera at the people in distress and those who were coming to their aid and began taking pictures. He was acting on instinct and doing what seasoned photographers do in moments of tranquility and chaos… he forever preserved the horrors and heroics that occurred that dreadful day so the world would forever recall the very worst and best of humanity.

A little more than two years after explosions shattered the Boston Marathon, jurors on Friday, May 15, 2015, returned a death sentence for the surviving bomber. In between, the city endured terror, a manhunt and lockdown, a painful trial and the start of healing, which continues. Now, Associated Press journalists who covered all aspects of this long ordeal have collaborated on a book, "The Boston Marathon Bombing: The Long Run from Terror to Renewal." The new AP Edition (www.ap.org/books), published in partnership with Mango Media, offers stories behind the story. Here is an excerpt:

On the cool, bright afternoon of April 15, 2013, near the marathon's blue-and-yellow finish line decal on Boylston Street, spectators were clapping and clanging cowbells for the stream of 27,000 runners. Each was someone's friend or spouse or significant other, parent, child, colleague or neighbor. Each was taking part for a reason: to set a personal best, to raise money for charity, or simply to experience the magic of America's most venerable footrace.

At 2:49 p.m., when the first deep boom sounded amid the happy din, it didn't immediately register to most people. They heard it, but to some, it sounded like the celebratory cannon fire that rings out over the Charles River every Fourth of July when the Boston Pops orchestra plays the "1812 Overture" outdoors. Nothing sinister.

When he heard it, Krupa was in the press room set up at the Fairmont Copley Plaza Hotel. He thought it must be a heavy piece of equipment falling. But 12 seconds later, there was another explosion.

Indoors, he couldn't hear the cheering turn to screaming, couldn't smell the stench of sulfurous smoke and burnt hair, couldn't see the people collapsed on the sidewalk or the spectators knocking over barricades in their rush to get away from blood-spattered Boylston.

Still, Krupa knew something was seriously wrong. As he scanned the press room, searching for clues, someone suddenly entered and announced that no one could leave.

 "We're in lockdown," the official said, as security guards took up posts at both main doors.

Then Krupa remembered: Behind the drapes near a podium was a door that led to another door to get out of the building. He grabbed three cameras, a laptop computer and a wireless transmitting device and ducked behind the drapes. Reaching the outside door as guards approached it, he sprinted from the hotel and onto Boylston Street.

Amid the commotion, he focused on three people a half-block away helping a stricken man in a wheelchair, Jeff Bauman, whose eyes locked on Krupa's.

"His face was ashen.... And as I got closer, I could see how shattered he was, that he had no legs, that these three people that were with him, they were going to get him the care he needed."

As they did, Krupa shot photos, then ran on, to the finish line, where again he climbed the photo bridge. The scene was ghastly.

"EMTs. Firefighters. Everybody was triaging all these people in a cluster," he said. Medical attendants and volunteers worked frantically, using their belts and shoelaces as tourniquets. Something else registered through his lens: Although the panicked were peeling away in every direction, a quarter of the crowd was running toward the blast sites to help.

Three people lay dead or dying — Lingzi Lu, a 23-year-old Boston University graduate student from China; Krystle Campbell, a 29-year-old restaurant manager from suburban Medford, Massachusetts; and Martin Richard, an 8-year-old boy from Boston's Dorchester neighborhood.

More than 260 others were wounded, scores of them moaning and dabbing at bleeding gashes. Sixteen clutched helplessly at legs that dangled from shreds of tissue or were simply gone; another had her mangled leg amputated months later.

This carnage was wrought, as the city and the world would learn, by the jagged shrapnel unleashed by twin pressure-cooker bombs. On Patriots' Day, terrorists had struck at Boston's heart.

Fear gripped the city. With the bomber — or bombers? — still on the loose, a no-fly zone was imposed over downtown Boston. The Bruins and Celtics canceled games.

Shortly after 6 p.m., President Barack Obama addressed the nation: "We will find out who did this. We'll find out why they did this. Any responsible individuals, any responsible groups, will feel the full weight of justice."

Investigators found nails, ball bearings and other shrapnel everywhere. They also found pieces of pressure cookers and the tattered remains of two black backpacks used to carry the bombs.

Krupa remembers the next 100 hours like this: "On Monday, the city was shattered physically. And as the week went on, there was a sort of shattering emotionally."

Rumors swirled and misinformation circulated among rival state and federal law enforcement agencies, some of it leaking to reporters. At one point, several news organizations, including AP, reported that a suspect was in custody. It was based on information from insistent authorities, but it was wrong.

Billy Evans, Boston's high-energy police superintendent who later would ascend to the top job of commissioner, had run the marathon for the 18th time Monday and was soaking in a hot tub afterward when he heard about the explosions. At first, he didn't believe it was terrorism — but reality sank in when he got to Boylston, where an hour earlier he'd been running. "To see the bodies lying in front of the Forum and the banners blown apart: It was a vision I don't think I'll ever get out of my head."

The rest of the week was a frenzied blur for him, but by Wednesday, he was told the FBI thought they had spotted the bombers on surveillance video.

On Thursday, three days after the bombings, the FBI called a news conference to release images of two men, their names still unknown. (It would be Friday before authorities identified the men they were hunting: brothers Tamerlan and Dzhokhar Tsarnaev.)

For now, suspect No. 1 was simply called "Black Hat." Suspect No. 2 was "White Hat." Grainy images showed them nonchalantly mingling with the crowd packing Boylston's sidewalks.

Their pictures were transmitted everywhere, and the manhunt intensified. It didn't take long to flush them out.

Within hours, Massachusetts Institute of Technology campus police officer Sean Collier was shot to death.

Soon afterward, a terrified carjack victim told authorities he had just escaped from two men — one claiming he had bombed the Boston Marathon and had just killed a police officer in Cambridge.

Police spotted the stolen Mercedes SUV in Watertown, and a firefight erupted.

A Watertown police officer later would testify that Tamerlan Tsarnaev emptied his gun, then threw it at him. Dzhokhar, behind the wheel of the stolen Mercedes, then drove straight at three officers who were trying to handcuff Tamerlan. Dzhokhar ran over his brother. Tamerlan died of gunshot wounds and injuries from being struck by the car.

But Dzhokhar escaped — simply vanished — managing to elude a massive police dragnet that gave normally carefree, collegiate Boston and its leafy environs a surreal quality in scenes broadcast live.

In an unprecedented announcement, Gov. Deval Patrick issued a "shelter-in-place" order for Boston and surrounding communities, instructing people to stay in their homes as the search continued. It had been Monday when the bombers struck; now it was Friday, and one of them was still out there, somewhere.

Jesse Bonelli, a young video game artist in Watertown, dutifully stayed inside his apartment. But just in case, he removed a decorative machete from a wall and sharpened it, explaining, "It's the only weapon I have. I want to be ready in case anyone bursts into the house."

After everything that had happened, he said, "I keep wondering what's next."

Finally, around 6 p.m., the governor lifted the shelter-in-place order, even though Tsarnaev hadn't been found.

When David Henneberry ventured outside his home on a quiet Watertown street, he noticed something amiss. The shrink wrap on his boat appeared loose. When he peered inside, he saw blood — then a man lying on his side.

Billy Evans raced to the scene and called for tactical backup, to prepare to get the man out of the boat. "The problem at that time is everyone had been searching for him for a long time. They had adrenalin pumping. People were coming from all directions. For whatever reason, someone let off a round. Once one let off a round, we had multiple shots fired," Evans said.

"I was screaming," he recalled in his thick Boston accent, "'Hold yah FI-YAH! Hold yah FI-YAH!'"

After the shots stopped, the FBI used flash grenades to try to flush Tsarnaev from the boat. Finally he climbed out, covered with blood.

Celebrations erupted in and around Boston. "I will always remember the feeling leaving Watertown," Evans said. "People were out waving flags, people were clapping like we had just won the war."

To read more, visit AP Books. 

Below is a selection of images from AP photographers following the aftermath of the Boston Marathon bombing. 

See more photos 

Text from the AP Book, The Boston Marathon Bombing: The Long Run from Terror to Renewal.

This book is currently free for a limited time. We invite you to download it today!

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