A video released by the Pakistan Taliban claims that a British extremist was one of the masterminds behind a devastating suicide attack on a CIA base in Afghanistan.
"Umar the British martyr" is identified in the 30-minute propaganda film, which pays tribute to extremists who have given their lives in attacks on Western or Pakistani forces.
It claims the Briton was a co-conspirator in an attack carried out by a Jordanian triple agent, Abu Dujana, on a US base in Khost, Afghanistan, three years ago.
He had been sent by the CIA and the Jordanian intelligence service to infiltrate al-Qaeda in Pakistan's tribal region but detonated a vest crammed with explosives when he arrived at Camp Chapman for a debriefing, killing the station chief, Jennifer Matthews, six other American personnel and his Jordanian handler.
The video, obtained by The Sunday Times(£), is the first time a Briton has been named in connection with the attack.
"Umar, with his accomplice Amir Hakimullah, entirely planned the suicide attack which Dr Abu Dujana undertook against the American CIA station in Khost," says an Urdu voice-over set to images of Umar's face.
Umar, whose full name is not given, is filmed sitting with Abu Dujana.
Speaking in English, with a London accent, he describes American forces as "dogs running with their tails in between their legs".
"By the grace of Allah, my brother Abu Dujana will attack them," he says.
The video claims he was arrested in the UK for "Jihadist" activities before heading to Afghanistan but was killed in a drone strike in 2010.
The attack on Camp Chapman was the CIA's bloodiest day in more than 25 years.
Abu Dujana, a doctor and Islamist blogger, had been recruited by Jordanian intelligence who believed he had been turned and would operate as a double agent, providing intelligence on the whereabouts of al-Qaeda's then deputy leader Ayman al-Zawahiri.
Officials later said he was not searched as he entered the base for fear of offending a trusted agent.
The Pakistani Taliban claimed responsibility with a video released two weeks after the attack, saying it was carried out in revenge for the drone strike that killed Baitullah Mehsud, their leader, months earlier.
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