Exploding underwear failed to detonate... because he had worn them for THREE WEEKS

The notorious underwear bomber who tried to bring down a jumbo jet on Christmas Day had a dirty little secret - he'd been wearing the explosive skivvies for weeks.

Umar Farouk Abdulmutallab wore them for three weeks to be exact, and it may have been the reason why he was unsuccessful in his 2009 terrorist plans aboard a Detroit-bound airliner.