A week after authorities intercepted packages in Dubai and England that were bound for the U.S., Al Qaeda in the Arabian Peninsula issued a message Friday saying it will continue to strike American interests.
Both mail bombs were wired to detonators that used cell phone technology.
U.S. officials have said they believe it was the Yemen group. The claim was reported by the private SITE Intelligence Group.
On Thursday the French Interior Minister said the bomb was defused at England's East Midlands airport. The White House said Thursday they could not confirm that.
"Al Qaeda gave us another warning," says Rep. Edward Markey, D-Mass. "They are obsessed with attacking us through the aviation sector."
Had things gone according to plan the UPS package could have been either on the ground in Philadelphia or on a plane to Chicago when the cartridge, packed with a pound of the explosive PETN, was set to explode.
A law enforcement source tells CBS News one idea being examined - the ignition source of the bomb - may well have been a cell phone battery coupled with the charge from the flash of its built-in camera.
"The cost would have been incalculable," says Markey. "We would be talking about a damage of tens or hundreds of billions of dollars to the U.S. and global economy."
CBS News has learned the intelligence community believes a half-dozen individuals or more representing core al Qaeda in the Arabian Peninsula may be responsible for initiating and orchestrating the attacks.
Despite the failed bombing attempts, an intelligence source tells CBS News al Qaeda sees the attacks as a success because of the chaos and fear they've created.