Officials say Umar Farouk Abdulmutallab has been discussing his contacts in Yemen and providing intelligence in multiple terrorism investigations.

Abdulmutallab has been known to federal authorities for at least two years and had been on a terror watch list compiled by the U.S. National Counterterrorism Center.

As federal authorities dissect what they're calling a terrorist attack, the rest of the world is left wondering how Abdulmutallab got into the country in the first place.