CNN Erin Burnett OutFront August 6, 2013 06:33:00
>> it was a new type of explosive that we had never seen and either attempted in the u.s. or around the world by terrorists. so all of our explosive detection equipment which screens over a million checked bags every day just in the u.s. wasn't calibrated to detect that. >> reporter: john pistole said that device had what he called a double initiation system. two syringes of chemical detonators instead of one. and, he says, al asiri encased that bomb in household caulk, so the explosive vapors couldn't be detected by machines or dogs. has this young mastermind trained others? >> i think the un...