Dr. Ron Walls at Brigham and Women's Hospital said that much of victims were injured by "street stuff" that got blasted during the explosions.
"Rocks, bits of metal, soda cans, anything that is really close to a blast like that can be fragmented," Dr. Walls said. "Everything we saw was ordinary material that could have been propelled by the device."
Dr. Peter Fagenholz said the case was similar for much of his patients at Massachusetts General Hospital. Fagenholz said that several amputations were performed and that at least one patient had a ruptured eardrum.
"A number of patients will require repeat operations tomorrow and serial operations over the next couple of days," he said.
Three people have been confirmed dead as a result of the attack and at least 144 people have been injured. Among the dead include 8-year-old Martin Richard who was standing near the finish line cheering for his father when one of the explosions took his life. He was in the third grade. His 6-year-old sister lost her leg in the blast. Also among the injured are a 9-year-old girl, a 7-year-old boy, a 12-year-old and a 2-year-old.
Many lost limbs after they were torn off from the explosions, leaving the streets covered in blood. It's reported that at least 144 people were being treated at hospitals with at least 17 in critical condition and 25 in serious condition. At least eights of the victims are children.