Underwear bomber Umar Abdulmutallab failed in his bid to blow up a transatlantic flight because he had been wearing the same pants for TWO WEEKS, it’s been revealed.

Nigerian Abdulmutallab was sentenced to life in prison without parole after he pleaded guilty to the Christmas Day 2009 plot, which saw him board an Amsterdam to Detroit flight with a bomb in his underwear.

Thankfully the explosives failed to fully detonate – something a US security official yesterday claimed was down to how long he had been wearing his pants.

Asked why Abdulmutallab’s attempt had failed, John Pistole from the Transportation Security Administration told the Aspen Security Forum: “He had had the device with him for over two weeks.”

His interviewer Catherine Herridge then asked if the device was “damp”, to which Pistole replied: “It was degraded... it’s efficacy was degraded.”

Herridge then quipped: “Thank God for bad hygiene.”

Abdulmutallab admitted his attempted attack was inspired by Anwar al-Awlaki, a radical American-born cleric and leading al Qaida figure who was killed by a US drone strike in 2011.

He admitted attempting use of a weapon of mass destruction and attempted murder.

•Text courtesy of Daily Mirror (UK). Photo shows failed bomber Umar Farouk Abdulmutallab.