The FBI has releaded a few crime scene images from Boston of what looks very much like a mangled pressure cooker.
A simple combination of gunpowder, a digital wrist watch, and a blasting cap can turn this container into a lethal bomb.
See more images the FBI released >
It's worth noting that several reports detail Al Qaeda's proliferation of how to build this bomb through their "Inspire" magazine in 2010. However, such knowledge has been published and republished since the Anarchist Cookbook in 1971.
SEE ALSO: This is what a pressure cooker bomb looks like >
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