Sky News 
Wednesday, May 9, 2012
The double agent who helped foil an al Qaeda plot to blow up a US-bound plane was a British national, possibly of Saudi origin, American officials have said.
The UK intelligence services played a central role in the operation that thwarted the plan to send a suicide attacker onto an aircraft with an underwear bomb, they added.
The foiled plot ended with the explosive device being delivered to the FBI, which is examining it.
The investigation involved MI5 and MI6, officials added.
The Obama administration had reportedly been under heavy pressure not to disclose the role of British authorities in the investigation.
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