Authorities no longer consider a 20-year Saudi to be a “person of interest” in the Boston bombings investigation. Al-Qaeda-type terrorists are still the suspected culprits based on the features of the attack, the design of the explosives and previous instructions from Al-Qaeda propagandists.
It is now confirmed that the explosives were made with pressure cookers. Fox News reports that “the style of the device used closely resembles that commonly seen in Afghanistan and Pakistan. “
In 2010, Al-Qaeda’s branch in Yemen, called Al-Qaeda in the Arabian Peninsula, published an English-language online magazine recommended using pressure cookers as “the most effective method” of creating explosives. It said to fill it with gunpowder and shrapnel, as the bombs in Boston were.