On Christmas Day 2009, Nigeria-born Umar Farouk Abdulmutallab attempted to detonate a bomb hidden in his underwear aboard a plane bound for Detroit.
Instead of detonating, the bomb caught on fire and airline crew and passengers were able to subdue him. Mr. Abdulmutallab told investigators that he received training from Al Qaeda associates in Yemen and met with several leaders, including Alwaki, the Monitor reported.