SANA'A, Yemen — For al-Qaida's affiliate in Yemen, the volunteer seemed ideal. He was willing to die in a suicide operation, and he had travel papers that would allow him to board a U.S.-bound flight.

It was a perfect dangle, in the parlance of spycraft, and al-Qaida in the Arabian Peninsula (AQAP) took the bait.

The group's bombmaker fitted the man with a new version of a nonmetallic "underwear bomb." What he didn't know was that the would-be martyr was an agent run by Saudi Arabia. And the man turned the device over to his Saudi handlers in Yemen.

The Saudis flew the bomb out of the country on a noncommercial jet and handed it over to U.S. officials in an unidentified third country, according to Mustafa Alani, director of security and defense studies at the Gulf Research Center in Jiddah, Saudi Arabia, who has close contacts with the kingdom's intelligence and counterterrorism agencies. A U.S. official confirmed aspects of his account.

The informant was one of several operatives sent into Yemen in the past two years with Western passports and other documents designed to attract the terrorist group's attention, U.S. and Western intelligence officials said Wednesday.

One official described the effort to disrupt the airline plot as part of a broader use of operatives with "clean skins" who can pass themselves off as militants capable of traveling into Europe or the United States.

As part of the effort, the Saudis have used fledgling al-Qaida operatives who were temporarily detained and individuals who have entered the country's rehabilitation program, which seeks to turn militants against terrorist groups.

The effort has focused on flipping low-level and aspiring jihadis, according to a former U.S. intelligence official familiar with the operation, revealed in news reports Monday.

When AQAP leaders tapped the informant for the latest assignment, the former agency official said, CIA and Saudi counterparts assembled plans to use him to recover the device.

The breakup of the bomb plot was followed by an airstrike Sunday that killed a senior militant in Yemen, Fahd al-Quso.

He was implicated in the 2000 bombing of the USS Cole, which killed 17 U.S. sailors.

Also Wednesday, U.S. officials said Director of National Intelligence James Clapper Jr. had ordered a review of leaks across all 16 agencies in the intelligence community to search for sources of information regarding the airline bomb plot.

A U.S. official said the Saudi informant in Yemen may have been pulled out of the country prematurely because of concern about public disclosures about the plot.