As people scramble after the first explosion at the Boston Marathon a second blast could be heard 15 seconds later.
Based on the images, former journalist in Iraq Danny Gonzalez says the bombs were likely anti-personnel Improvised Explosive Devices, or IEDs.
“Typically, explosives that are lined or covered with small bits of medal like screws, ball bearings, kitchen utensils so that when the IED explodes, it creates shrapnel that cuts people up and breaks off limbs,” said Gonzalez.
While overseas, Gonzalez was placed in one of the safest buildings and yet he could hear the IEDs loud and clear.
“You could still feel the walls shaking. Stuff on your shelves were bouncing up and down and you could feel it in your heart,” Gonzalez said..
Although it is not confirmed what the bombs were made of, Navy Intelligence Specialist Scott Raab said most IEDs are made of Calcium Immonium Nitrate – better known as fertilizer. The same type responsible for the Oklahoma City bombing in 1995.
“IEDs are usually built by people who do not have the necessary skills to make more advanced weapons. It is likely sometimes you see IEDs explode, sometimes they don’t explode,” Raab said.
Officials described the Boston bombs as “small portable devices.”
“We are reminded by today’s actions that that is what our troops deal with every single day. It is not pretty. It is a horrible disputable act,” said Raab.
The Boston bombs killed three innocent lives and injured more than 100.