U.S. Hunts Devious Al Qaeda Bomb Maker's Proteges
Al Qaeda's most diabolical bomb maker,
who has targeted the American homeland
at least four times, has trained other
terrorists who are now being hunted
down, the top U.S. aviation security
official said today.
Transportation Security Administrator
John Pistole told ABC News during a
discussion at a counterterrorism
conference that accused Saudi terrorist
Ibrahim al-Asiri had shared his expertise
at building almost undetectable bombs
with a number of al Qaeda operatives.
"There is intel that he has unfortunately
trained others," Pistole said at the annual
Aspen Security Forum.
Asiri, 31, created two versions of an
improvised explosive device hidden in
men's underwear, with which the Yemen-
based al Qaeda affiliate al Qaeda in the
Arabian Peninsula (AQAP) almost
succeeded in blowing up a passenger jet
over Detroit on Christmas Day 2009. A
"new and improved" version was
obtained by spy agencies last year.
Pistole said that "there is a lot of effort to
identify" those to whom Asiri has taught
his terror tradecraft, particularly after
similar liquid explosives bombs were
discovered aboard U.S.-bound cargo jets
However, "talent is not always
transferable," a U.S. counterterrorism
official told ABC News recently, meaning
that Asiri's skills as a bomb innovator are
Pistole also for the first time detailed the
sophisticated "Underwear Bomb II,"
which a double-agent stole from AQAP in
2012 after the group dispatched him as a
suicide bomber aboard an aircraft. ABC
News obtained a Department of
Homeland Security illustration of the
newer bomb. Pistole called the U.S. ally-
led operation an "intelligence coup,"
because it enabled western
counterterrorism services to thwart a
serious threat from a bomb almost
impossible to detect by magnetometers
and advanced imaging machines at
"It was a new type of explosive we had
never seen," which used two redundant
initiators filled with liquid explosives to
detonate a larger liquid explosive charge
in men's briefs, Pistole said.