Some of the British-born Muslims have apparently joined Taliban in fighting against British troops in Afghanistan.
According to official sources, thick Midlands and Mancunian accents have been picked up from enemy radio signal in the war zone in Afghanistan earlier.
But now there is fresh evidence that some of the Taliban militants were raised in the UK with the revelation that one fighter killed in a battle had an Aston Villa football club tattoo on his body.
"It was a shock to hear that the guys we were fighting against supported the same football clubs as we did, and maybe even grew up on the same streets as we lived," a military source said.
The source said the body of the unidentified Muslim insurgent was found with the AVFC tattoo following clashes with the NATO-led International Security Assistance Forces.
The discovery adds to fears the Taliban is successfully recruiting hundreds of radicalised British nationals to fight against the country of their birth.
Tory MP Patrick Mercer, a former infantry commander, said the presence of a tattoo of an English football club suggested the insurgent had at one point been a well-integrated member of UK society, who identified with his home culture, but was radicalised nevertheless.
Allied spy planes have previously picked up Birmingham and Manchester accents among Taliban radio chatter, while in April it emerged that a Briton had been identified as a Taliban bombmaker after his fingerprints were found on an unexploded roadside device in Helmand.