NEW YORK (CBSNewYork) -- Al-Qaeda in the Arabian Peninsula trained in the desert, but was planning on blowing up a U.S.-bound jet. However, the plot was undone by a man they thought was one of their own, CBS News has learned.
"The individual who was to carry the bomb on the plane was an intelligence source," CBS News security expert John Miller told CBS 2's Sean Hennessey on Tuesday night.
Miller, a former national intelligence deputy director, said the double agent was a Saudi operative posing as a suicide bomber cooperating with the CIA and had been infiltrating Al-Qaeda in the Arabian Peninsula for some time.
"This is an extraordinary victory. One of the most difficult things to do and one of the most reliable sources is to have an actual human source who can penetrate a closed secretive organization," Miller said.
The secretive organization's bomb-making mastermind, Ibrahim al-Asiri, is suspected of crafting a non-metallic device that would have gotten past airport metal detectors and might have been spotted by the full body scanners, officials have said. Experts said the latest device is a sophisticated upgrade from the underwear bomb al-Asiri made that failed to explode aboard a Detroit airliner in 2009.
"This is a very clever guy," former CIA officer Bruce Riedel told CBS 2's Don Dahler.
Clever and determined.
"They keep trying to find more and more perverse and terrible ways to kill innocent people," Secretary of State Hillary Clinton said.
"He has the assets, he has the intent, and he has no conscience," retired NYPD Bomb Squad detective Kevin Barry added.
Barry has examined al-Asiri's work and said he sees one thing.
"An increased sophistication at trying to prevent being detected. They're making mistakes but not big mistakes, but we've been fortunate that they've been caught," Barry said.
When asked how terrorists could have improved the 2009 bomb, Barry said, "Improvement is going to have to be in the chemical mixture and the improvised detonator. That's what failed."
That this plot was foiled by a double agent is a double-edge sword, Miller said.
"The bad news is, you had a source inside the organization that had access to its planning cycle, and you might not have that now," Miller said.
1010 WINS' Terry Sheridan reports
The terrorists are learning from their mistakes. The newest underwear bomb was designed to avoid detection at checkpoints because it contains no metal, only plastic explosive.
The Transportation Security Administration said its nearly 700 full-body scanners located at airports around the world can detect non-metal threats, but not everyone trusts them, including Israel, which prefers other detection methods, such as profiling and physical inspections.
It won't use that term, but the TSA has its own type of profiling, called "controlled cognitive engagement" interviews, in which travelers fitting certain characteristics are taken aside for questioning. There are also security cameras watching passengers waiting at airports, and undercover agents listening in on conversations and noting suspicious behavior. Barry said there's even more to security than is publicly known.
"The security people don't tell everyone everything because then intel is not intel, it's only information," he said.
But Long Island Congressman Peter King, Chairman of the Homeland Security Committee, said the U.S. has to stay ahead of the terrorists.
"I can assure you that the TSA and security generally is going to be looking very, very carefully at this to see what steps, if any, we have to take to upgrade our defenses against this type of attack," Rep. King said.
Security officials said Tuesday that airport procedures don't need to be toughened despite this bomb plot because the current U.S. detection methods would likely have spotted the shape of the explosive. However, the TSA is sending guidance to some international airports about how to detect these new kinds of bombs.
At LaGuardia Airport, passengers are no longer surprised by the news that terrorists are plotting to blow up planes.
Still, as word of yet another close call trickles out, many can't help but be a little anxious as they prepare to take off their shoes and belts and walk through security.
"Well, I'm very scared and very worried about it," one passenger told CBS 2's Kathryn Brown.
"We have to get from A to B and if we have to get an extra pat down before we go through to get there safely, that's all that matters," said another passenger.
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