San'a, Yemen Yemeni police arrested a woman on suspicion of mailing a pair of bombs powerful enough to take down airplanes, officials said Saturday as details emerged about a terrorist plot aimed at the U.S. that exploited security gaps in the worldwide shipping system.
Investigators were hunting Yemen for more suspects tied to al-Qaida and several U.S. officials identified the terrorist group’s top explosives expert in Yemen as the most likely bombmaker.
The explosives, addressed to Chicago-area synagogues, were pulled off airplanes in England and the United Arab Emirates early Friday morning, touching off a tense search for other devices.
It still wasn’t clear whether the bombs, which officials said were wired to cell phones, timers and power supplies, could have been detonated remotely while the planes were in the air, or when the packages were halfway around the world in the U.S. But the fact that they made it onto airplanes showed that nearly a decade since the Sept. 11, 2001, attacks, terrorists continue to probe and find security vulnerabilities.
The packages were addressed to two synagogues in the Chicago area. But British Prime Minister David Cameron said Saturday that he believes the explosive device found at the East Midlands Airport in central England was intended to detonate aboard the plane.
British Home Secretary Theresa May added that the bomb was powerful enough to take down the plane. A U.S. official said authorities believe a second device found in Dubai was similarly potent.
Yemeni President Ali Abdullah Saleh told reporters that the United States and United Arab Emirates had provided intelligence that helped identify the woman suspected of mailing the packages.
A Yemeni security official said the young woman was a medical student and that her mother also was detained.
The police action was part of a widening manhunt for suspects believed to have used forged documents and ID cards, Yemeni officials said. One member of Yemen’s anti-terrorism unit said the other suspects had been tied to al-Qaida.
The officials, like many in the U.S., spoke on condition of anonymity to discuss the ongoing investigation unfolding on three continents.
Al-Qaida’s Yemen branch, known as al-Qaida in the Arabian Peninsula, took credit for a failed bombing aboard a Detroit-bound airliner last Christmas. The bomb used in that attack contained PETN, an industrial explosive that was also used in the mail bombs found Friday.
The suspected bombmaker behind the Christmas Day attack, Ibrahim Hassan al-Asiri, is also the prime suspect in the mail bomb plot, several U.S. officials said. Al-Asiri also helped make another PETN device for a failed suicide attempt against a top Saudi counterterrorism official last year. The official survived, but his attacker died in the blast.
“The forensic analysis is under way,” President Barack Obama’s counterterror chief John Brennan said Friday. “Clearly from the initial observation, the initial analysis that was done, the materials that were found in the device that was uncovered was intended to do harm.”
Officials said the plot was discovered thanks to intelligence passed from Saudi Arabia. Without that tip, it’s unclear whether anyone would have discovered the bombs before they were airborne — or on U.S. soil.
The U.S. already had been on the lookout for a such a plot, having received indications that the Yemeni-based al-Qaida faction was interested in “exploring an operation involving cargo planes,” a U.S. counterterrorism official said.
U.S. authorities then acted quickly after receiving a tip “that suspicious packages may be en route to the U.S” — specifically Chicago — the official said, speaking on condition of anonymity to discuss intelligence matters.
Currently, American officials do not get details about the contents of a U.S.-bound cargo plane until four hours before it’s scheduled to land. In the case of long distance flights, those planes would already be airborne. Once a plane lands, officials screen packages that they feel warrant a closer look.
The U.S. temporarily banned all incoming cargo and mail from Yemen. A UPS employee in Yemen said the office has temporarily halted receiving any packages for delivery.