An injured man is loaded into an ambulance after two explosions during the 117th Boston Marathon near Copley Square on Monday.
Jim Rogash/Getty Images
Aaron Michael, a witness, told member station WGBH that he heard first one explosion and then another.
"Boom, there was black smoke," he said. "Mass chaos. I saw one woman really, really badly hurt. She was being carried out by people, she was bleeding pretty badly. It wasn't a good scene. It was awful."
WGBH's Anne Mostue said she heard two very loud explosions, and then immediately after, she saw "people screaming and running toward the river."
Boston Herald reporter Chris Cassidy, who was running in the marathon, said he heard two explosions: "The first one was beyond the finish line. I heard a loud bang and I saw smoke rising.
"I kept running and I heard a loud bang. It looked like it was in a trash can or something," Cassidy said. "There are people who have been hit with debris, people with bloody foreheads."
The Boston Globe's David Abel, who has reported from war zones in the past, was at the finish line taking video of the runners when the explosions occurred. He described what followed as "the worst thing I've ever seen in my life.
"There were people lying on the ground, mangled, blood, glass shattered," he said. "It was really chaos."
"People missing limbs, and it appeared that the blast shattered windows," he said.
He said it took about 10 minutes for emergency services personnel to start getting the wounded away from the scene. He said he saw children injured and that first responders "treated dozens of people with trauma ... they were stabilized and put on ambulances." (The video below was shot by Abel immediately after the explosions.)
Jackie Bruno, a reporter for New England Cable News, tweeted: "Runners were coming in and saw unspeakable horror." She also posted a photograph showing one man lying on the ground, blood all over his legs.
Timothy Quinlan, a volunteer security officer told NPR's Adam Davidson that the first explosion — as loud as a cannon — came from ground level, and that he had seen dead bodies and body parts amid the debris. He said he did not see any of the runners injured.
Bruce Gellerman, a reporter with member station WBUR in Boston, said "scores and scores of ambulances" were on the scene and that everyone, including reporters, was being pushed away from the scene of the explosions.
There are "people crying, people sitting collecting their thoughts. Some of the runners are still shaking," Gellerman said about an hour after the explosions.
The Associated Press quoted one woman as saying she was waiting for her husband to cross the finish line and, in her words, "It just blew." She said the explosion was "a loud boom, and then glass everywhere."
Cherie Falgoust told the AP that something hit her in the head and she "just ducked," while runner Laura McLean of Toronto described people who were "really, really bloody."