The reports said that Al Qaeda had completed a sophisticated new, nonmetallic underwear bomb last month and that the would-be suicide bomber actually was a double agent working with the CIA and Saudi intelligence agencies.

The would-be suicide bomber secretly turned over the group's most up-to-date underwear bomb to Saudi Arabia, which gave it to the CIA. Before he was whisked to safety, the spy provided intelligence that helped the CIA kill Al Qaeda's senior operations leader, Fahd al-Quso, who died in a drone strike last weekend.

In an appearance Wednesday before the House Judiciary Committee, FBI Director Robert Mueller said the FBI is examining the explosive device. He said the scheme hatched in Yemen demonstrates that it's essential for Congress to reauthorize counterterrorism tools enacted in 2008. Some of these programs expire at year's end.

A spokesman for the AP, Paul Colford, said in a statement that the news organization "acted carefully and with extreme deliberation in its reporting on the underwear bomb plot and its subsequent decision to publish."