The latest plot to bomb a U.S. airliner has been foiled, but U.S. intelligence officials have described the bomb as a sophisticated device that's believed to be the work of al-Qaida in the Arabian Peninsula. Many details are still not available, but here's what is and isn't known so far:
The Plot: The plan originated in Yemen, home of al-Qaida in the Arabian Peninsula, or AQAP. NPR's Dina Temple-Raston says her sources confirmed that the bomber had been instructed to choose a U.S.-bound flight to target, but that he had not yet bought his tickets. The Associated Press broke the story Monday, and U.S. officials have provided additional details.
The Mole: Temple-Raston reports that the CIA had a source who was inside an al-Qaida bomb cell in Yemen. She quotes sources as saying the informant brought the bomb out of Yemen and that it ended up in the hands of intelligence officials. What the sources are not making public is where the bomb was taken and how it came into the possession of U.S. intelligence. The insider is now said to be safely out of Yemen.
The Intelligence Payoff: In addition to whatever the experts can glean about the state of al-Qaida's bomb-making art, the operation may have yielded other information. Temple-Raston notes that the reputed head of al-Qaida in Yemen, Fahd al-Quso, was killed by a U.S. missile on Sunday. She says it's unclear whether the insider provided information that helped locate Quso.
Similarities To 2009 Case: The scheme sounds very much like the "underwear bomber" who tried to blow up Northwest Airlines Flight 253 on Christmas Day in 2009. The latest case also called for equipping a suicide attacker with an explosive device that could be concealed in his underwear.
The Bomb: The bomb is now at the FBI's explosives lab in Quantico, Virginia where experts are dissecting it. It apparently did not contain any metal, and therefore may have passed unnoticed through airport security. Temple-Raston reported that intelligence experts believe the latest bomb was a more sophisticated version of device used in 2009.
The Suspected Bombmaker: This bomb, like the one in 2009, is believed to be the work of a 28-year-old Saudi named Ibrahim Hassan al-Asiri. The latest bomb bears the hall-marks of Asiri's work, and appears to be an effort to improve on technology that failed the first time around, Temple-Raston reports. One thing that concerns intelligence officials, she says, is that Asiri may well have trained other people, and that the latest bomb is the work of one of his protégés.
Uncovering The Plot: It's not clear exactly how or when intelligence officials learned about the plot. However, President Obama was informed of the case last month, according to Caitlyn Hayden, a spokeswoman for the National Security Council.
Update at 4:51 p.m. ET. Just a quick note to let you know that we've written through this post to reflect new reporting.