The British jihadist who beheaded an American journalist is believed to be a senior Isis militant capable of inspiring followers to wreak havoc on his home soil.
The man, who appears to have experience of decapitations, is a prime target for MI5, MI6 and the SAS amid fears that he could kill again after his new-found infamy.
James Foley, a photographer from New Hampshire who was captured by militants in 2012, was killed by the Briton in a video that was broadcast around the world on Tuesday night.
The killer, named by a former hostage as “John” and described by David Cameron as likely to be a British citizen, has been linked to a group of four British-Pakistani jailers for the Islamic State (Isis).
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