U.S. intelligence officials warn that the same al Qaeda group that attacked a U.S. airliner on Christmas Day has also trained female suicide bombers [1]to attack Western targets, ABC News reports.

An intelligence official told investigative reporter Brian Ross that Al Qaeda in the Arabian Peninsula (AQAP), a jihadist organization based in Yemen, has trained female suicide bombers of a "non-Arab" appearance traveling on Western passports. The same terrorist organization trained the 23-year-old Nigerian Umar Farouk Abdulmutallab, a jihadist recruit that smuggled explosives in his underwear onboard Detroit-bound Northwest Flight 253 and tried to detonate them on Christmas Day.

If AQAP has trained and dispatched female suicide bombers, it's more evidence the terrorist organization actively recruits individuals that do not fit a typical jihadist profile. A phenomenon counterterrorism officials and experts call "clean skins."

"There are others who are still out there who have been trained and who are clean skins," former White House counterterrorism official Richard Clarke told ABC News, "that means people who we do not have a record of, people who may not look like al Qaeda terrorists, who may not be Arabs, and may not be men."

These new reports come immediately after the Senate Committee on Foreign Relations last week released a report describing approximately 72 Americans, some ex-convicts, who may have traveled to Somalia and Yemen [2]to train with jihadist organizations affiliated with al Qaeda.

These threat warnings come at the same time that U.S. security officials last week reported an uptick in suspicious activity within the U.S. aviation sector, ABC News reports.

The alert comes during a week in which American law enforcement officials described an "unusually high" number of people on the no-fly list attempting to board flights to or in the United States.

At least six people on the no-fly list were denied boarding in a 48-hour period between Saturday and Monday this week, according to the officials.

Two of the six were stopped at London's Heathrow Airport.

On Friday, the United Kingdom raised its terror alert system from "substantial" to "severe" [3] based on intelligence that al Qaeda has planned a wave of attacks on Western targets, reports the Telegraph.The decision to raise the terror alert level means U.K.-based attacks were "highly likely," although not "imminent," according to Home Secretary Alan Johnson [4].

FBI personnel that questioned Abdulmutallab said that he warned them that there were more radicalized people like him [5] planning attacks against the United States.

♦ Photo of women inside airport terminal by quinn.anya/Flickr [6]

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