Boy, 8, one of 3 killed in bombings at Boston Marathon; scores wounded

Updated 10:25 AM EDT, Thu April 18, 2013

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"

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(CNN) —  

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