FBI confirms leak probe on al-Qaida plot

FBI Director Robert Mueller said Wednesday the bureau has launched an investigation into who leaked information about an al-Qaida plot to place an explosive device aboard a U.S.-bound airline flight.

In an appearance before the Senate Judiciary Committee, Mueller said a leak like this one threatens ongoing operations, "puts at risk the lives of sources, makes it much more difficult to recruit sources" and damages relationships with law enforcement partners from other countries.

The Associated Press and other news organizations revealed details of the plot this month. A double agent working with the CIA, Saudi intelligence agencies and the British intelligence agency MI6 turned the bomb over to the U.S. government. Mueller's comment to the Senate Judiciary Committee was the first on-the-record confirmation that a Justice Department leak probe is under way.

"We have initiated an investigation into this leak" and "will investigate thoroughly," said Mueller.