Story highlights

New measures feature additional random checks after passengers make it through security

AQAP's leadership says lone wolf attacks that hit the U.S., West are a priority

Terrorists' Inspire magazine stated that even if new devices were detected or failed, they would bring terror to the West

Counterterrorism officials have been concerned about technical instruction provided by Inspire for years

CNN  — 

The Department of Homeland Security is increasing security checks at American airports because of concerns over new bomb-making instructions released by al Qaeda in Yemen (AQAP), the terrorist group which U.S. intelligence agencies believe may have been behind the Charlie Hebdo attack in Paris, U.S. officials tell CNN.

They say the new measures will feature additional random checks after passengers make it through security and will include passenger pat-downs, bag checks and hand swabs for traces of explosives.

The new issue of AQAP’s Inspire magazine, released on December 24, featured instructions on how to build what AQAP called a “hidden bomb” from easily purchasable materials. It also included directions on how would-be lone wolves worldwide can evade airport security scanners and sniffer dogs.

In recent months, AQAP’s leadership has repeatedly stated hitting the United States is a priority. The new issue of Inspire made clear it viewed lone wolf attacks by its supporters in the West as an increasingly important part of these efforts.

The magazine claimed the recipe was for a simplified version of the device used in an attempt to blow up a U.S. passenger jet over Detroit five years ago.

On Christmas Day 2009, Omar Farouk Abdulmutallab, the so-called “underwear bomber,” attempted to detonate an explosive device built by Ibrahim al Asiri, AQAP’s master bomb-maker, on a flight from Amsterdam to Detroit. The main charge – a white powdery explosive called PETN which airport security scanners at Amsterdam airport did not detect – failed to detonate as the plane approached Detroit.

The new recipe does not involve the manufacture of PETN, a substance difficult for extremists to manufacture or obtain in the West. Instead, it contains similarities to a bomb formula put out by the group in the first issue of Inspire in 2010 called “Make a Bomb in the Kitchen of Your Mom.” That recipe was downloaded and used by the Boston bombers and several other extremists in plots on both sides of the Atlantic.

In the new issue, AQAP suggested its external operation division had greenlighted sharing the recipe because al Asiri and his team had developed a new generation of more sophisticated devices.

What is AQAP?

In 2012 Saudi and Western intelligence foiled a plot by AQAP to bomb a U.S. plane with an updated version of the underwear device.

It is not clear if the recipe is viable or if it would have enough explosive power to endanger an aircraft. Nor is it clear if the device would have any chance of getting through explosive scanners at airport security.

U.S. officials and explosive detection experts tell CNN that advanced detection equipment, including body scanners, should catch even previously hard-to-detect explosives like PETN, even if detection experts say they don’t provide a 100% guarantee. But U.S. officials say advanced body-scanning technology is not available in some smaller U.S. airports.

The authors of the latest issue of Inspire magazine claimed that if enough lone wolves launch attempts with their suggested device, some would get through.

The magazine stated that even if the devices were detected or malfunctioned they would bring terror to the West.

The key aim, the group stated, was to undermine the American economy. It listed several American airline companies, as well as British and French carriers as targets. It said that lone wolves should claim responsibility by writing emails timed to be distributed after their operations.

In the 112-page issue the group also mentioned recent lone wolf attackers in Canada, the United States, Australia and France, calling a hatchet attack on NYPD police officers in Queens in October “splendid.”

Counterterrorism officials on both sides of the Atlantic been concerned about technical instruction provided by Inspire magazine for several years.

In August 2013 the British security agency MI5 revealed to the UK parliament’s intelligence and security committee that “Inspire” has been “read by those involved in at least seven out of the 10 attacks planned within the UK since its first issue (in 2010). We judge that it significantly enhanced the capability of individuals in four of these 10 attack plots.”

Magazine story on bomb making prompts airport searches