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Story highlights
A third person has died from the bombing, Boston Police Commissioner Ed Davis says
An 8-year-old boy was one of those killed
The bombs were small, with no initial sign of high-grade explosive material, an official tells CNN
Obama vows those guilty "will feel the full weight of justice"
Two bombs struck near the finish line of the Boston Marathon on Monday, turning a celebration into a bloody scene of destruction.
Boston Police Commissioner Ed Davis said Monday night that the death toll had risen to three. Scores were injured at the scene.
One of the dead was an 8-year-old boy, according to a state law enforcement source.
Hospitals reported at least 144 people are being treated, with at least 17 of them in critical condition and 25 in serious condition. At least eight of the patients are children.
At least 10 people injured had limbs amputated, according to a terrorism expert briefed on the investigation.
Several of the patients treated at Massachusetts General Hospital suffered injuries to lower limbs that will require “serial operations” in the coming days, trauma surgeon Peter Fagenholz said Monday night. Some injuries were so severe amputations were necessary, Fagenholz added.
Full horror of the day emerges in emergency rooms
In Washington, President Barack Obama vowed, “Any responsible individuals, any responsible groups, will feel the full weight of justice.”
Boston “is a tough and resilient town,” he said, adding that Americans will stand by Bostonians “every single step of the way.”
‘Like a huge cannon’
The terrorist attack, near the marathon’s finish line, triggered widespread screaming and chaos, shattered windows and barricades and sent smoke billowing into the air at Copley Square.
The blasts were about 50 to 100 yards apart, officials said, on a stretch of the marathon course lined with spectators cheering runners through the final yards of a 26-mile, 385-yard endurance feat.
“It felt like a huge cannon,” a witness told CNN about one of the blasts.
Allan Panter, a doctor who was near the finish line waiting for his wife to finish the race, told CNN he was standing about 20 to 25 feet from the first blast. He said he treated victims on the street after the explosion.
“I saw at least six to seven people down next to me,” he said. “They protected me from the blast. One lady expired. One gentleman lost both his (lower) limbs. Most of the injuries were lower extremities.”
Flights banned over Boston Marathon blast site
Bill Iffrig, 78 and a veteran marathoner, was nearing the finish when “the shock waves just hit my whole body and my legs just started jittering around.” Iffrig, who can be seen in video of the explosion wearing an orange tank top, was helped to his feet by an event volunteer and had just a scratch from his fall, he told CNN.
Federal authorities are classifying the bombings as a terrorist attack, but it’s not clear whether the origin was domestic or foreign, a federal law enforcement official with knowledge of the investigation said.
A federal law enforcement official told CNN that both bombs were small, and initial tests showed no C-4 or other high-grade explosive material, suggesting that the packages used in the attack were crude explosive devices.
Another explosive device found
Authorities in Boston found at least one other explosive device that they were dismantling, Boston Police Commissioner Ed Davis said.
Rep. Bill Keating of Massachusetts, meanwhile, said two more were found.
One unexploded device was found at a hotel on Boylston Street near the bomb site and another unexploded device was found at an undisclosed location, Keating, a Democrat and member of the House Homeland Security Committee, said. He called the bombing a “sophisticated, coordinated, planned attack.”
FBI to take lead in investigation, seeks bomb ‘signature’
It was unclear who may have planted the marathon bombs. There were no credible threats before the race, a state government official said.