The plot was thought to be a follow-up to the airline bomb attempt that was foiled in 2009. Officials: Bomber-to-be was informant

WASHINGTON (AP) — Over the past three years, al-Qaida bomb makers in Yemen have developed three fiendishly clever devices in hopes of attacking airplanes in the skies above the United States.

First, there was the underwear bomb that fizzled over Detroit on Christmas 2009. Next, terrorists hid bombs inside printer cartridges and got them on board cargo planes in 2010, only to watch authorities find and defuse them in the nick of time.


Then last month, officials say, al-Qaida completed a sophisticated new, nonmetallic underwear bomb — and unwittingly handed it over to the CIA.

The would-be suicide bomber, the man al-Qaida entrusted with its latest device, actually was a double agent working with the CIA and Saudi intelligence agencies, officials said Tuesday. Instead of sneaking it onto a plane in his underwear, he delivered it to the U.S. government and handed al-Qaida its latest setback.

The extraordinary intelligence operation was confirmed by U.S. and Yemeni officials who were briefed on the plot but spoke on condition of anonymity because they were not authorized to discuss it.

The FBI is still analyzing the explosive but officials described it as an upgrade over the Christmas Day bomb. This new device contained lead azide, a chemical known as a reliable detonator. After the Christmas attack failed, al-Qaida used lead azide as the detonator in the 2010 plot against cargo planes.

Security procedures at U.S. airports Tuesday remained unchanged despite the plot, a reflection of both the U.S. confidence in its security systems and a recognition that the government can't realistically expect travelers to endure much more. Increased costs and delays to airlines and shipping companies from new security measures could have a global economic impact too.

Security officials said they believe airport security systems put in place in the United States in recent years could have detected the new device or one like it. But the attempt served as a stark reminder that security overseas is quite different.

"I would not expect any real changes for the traveling public," House Intelligence Committee Chairman Mike Rogers, R-Mich., said. "There is a concern that overseas security doesn't match ours. That's an ongoing challenge."

While airline checks in the United States mean passing through an onerous, sometimes embarrassing series of pat-downs and body scans, procedures overseas can be a mixed bag. The U.S. cannot force other countries to permanently adopt the expensive and intrusive measures that have become common in American airports over the past decade.

The Transportation Security Administration sent advice Tuesday to some international air carriers and airports about security measures that might stave off an attack from a hidden explosive. It's the same advice the U.S. has issued before, but there was a thought that it might get new attention in light of the foiled plot.

The U.S. has worked for years to try to improve security for U.S.-bound flights originating at international airports. And many countries agree that security needs to be better. But while plots such as the Christmas attack have spurred changes, some security gaps that have been closed in the U.S. remain open overseas.

Officials believe body scanners, for instance, probably would have detected this latest attempt by al-Qaida to bring down a jetliner. Such scanners allow screeners to see objects hidden beneath a passenger's clothes.

But while scanners are in place in airports nationwide, their use is scattershot overseas. Even in security-conscious Europe, the European Union has not required full-body imaging machines for all airports, though a number of major airports in Paris, London, Frankfurt, Germany and elsewhere use them.

All passengers on U.S.-bound flights are checked against terrorist watch lists and law enforcement databases.

In some countries, U.S. officials are stationed in airports to offer advice on security matters. In some cases, though, the U.S. can do little more than hope that other countries follow the security advice from the Transportation Security Administration.

"Even if our technology is good enough to spot it, the technology is still in human hands and we are inherently fallible," said Rep. Adam Schiff, D-Calif., a member of the House Intelligence Committee. "And overseas, we have varying degrees of security depending on where the flight originates."

Authorities believe that, like the Christmas bomb and the printer bombs, this latest device is the handiwork of either al-Qaida's master bomb maker in Yemen, Ibrahim Hassan al-Asiri, or one of his students.

In the meantime, Americans traveled Tuesday with little apparent concern.

"We were nervous — for a minute," said Nan Gartner, a retiree on her way to Italy from New York's John F. Kennedy Airport. "But then we thought, we aren't going anywhere near Yemen, so we're OK."