Pressure-cooker bombs used in Boston attacks point to possible Islamic connection

Breaking news from sources familiar with the investigation reveals a significant new detail about the bombs used in yesterday's Boston Marathon terror attack — they were made out of pressure-cookers:

The two bombs that killed three people and injured at least 176 at the Boston Marathon on Monday were made from six-liter pressure cookers crammed with shards of metal, nails and ball bearings and stashed in black duffel bags, police sources revealed today.

Why is this significant? Because this exact bomb concept is a signature design used by Islamic groups in the Middle East/central Asia:

The cruelly-designed bombs have 'frequently' been used in Afghanistan, India, Nepal and Pakistan, according to a 2010 Homeland Security Department pamphlet - hinting at the origins of the bombers behind the worst terrorist atrocity in the U.S. since 9/11.

A similar device was used in the failed attempt to bomb Times Square by Faisal Shazad in 2010. It is a preferred weapon of al-Qaeda terrorists and listed as the 'most effective' weapon of jihad, according to in an English language terror magazine called Inspire.

To my knowledge, the pressure-cooker bomb design has never been used in the U.S. by any group other than jihadist groups (if you have information otherwise, please post it in the comments section).

The Smoking Gun has digital copies of the Homeland Security press release warning of pressure-cooker bombs, issued in 2010:

[Click image to see it full-size.]