Boston bombs were made of pressure cookers with schrapnel and ball bearings
The FBI has shared images of one of the explosives, which was stored in a black nylon backpack
The explosives detonated at the Boston marathon bombings are believed to have been made from “pressure cookers and schrapnel” which was detonated by a mobile phone, according to US reports.
Doctors treating the 176 victims injured at various hospitals throughout Boston have revealed that several patients have pellets, nails and sharp metal objects embedded in their skin, with some victims having “40 or more” fragments each.
George Velmahos, the Chief of Trauma Surgery at Massachusetts General Hospital said: “Many of them have severe wounds mostly in the lower part of their body – wounds related to the blast effect of the bomb, as well as small metallic fragments that entered their bodies – pellets, shrapnel, nails – that these bombs had.”
“I wouldn't exclude completely the possibility that some of these fragments are environmental, but my opinion is that most of them were in the bomb,” he added.
“They are numerous. There are people who have 10, 20, 30 or 40 of them in their body or more.”
Authorities have said that the two bombs were placed in dark coloured backpacks, before being detonated remotely - believed to be by mobile phone - and have released photos of one of the devices. One of the bombs was reportedly placed inside a black nylon backpack and then dumped in a garbage can.