Undercover informant in foiling of underwear bomb plot was British citizen

The undercover informant in the foiled underwear bomb plot linked to al Qaeda's Yemeni affiliate was a British citizen, possibly of Saudi origin, US counter-terrorism officials said.

British intelligence played a central role in the operation that foiled the plot to send a suicide bomber onto an airplane, and it was a cooperative effort between MI5 and MI6, Britain's domestic and foreign intelligence services known, officials told Reuters on condition of anonymity.