Koka has had a Nato makeover. As he stares out from a British poster in Musa Qala, tending a wounded civilian, it is not just his beard and hair — once more reminiscent of a Barbary Corsair than a police commander — that have been trimmed and combed. His whole past has been reinvented.

“We're lucky to have Koka here,” Captain Chris Howard, the British psychological operations officer who produced the poster, said. “We've kind of turned him into a celebrity.”

Other posters decorating the bazaar's notice board have superimposed a photo of Koka and his men receiving their police training certificates on to a cinema screen. The seated audience is Western. “They are not actors. They are real policemen now,” the caption elaborates.

Musa Qala's farmers and tradesmen could be forgiven for thinking that their police chief's career is indeed celebrity news. Yet his past makes him an unlikely choice as a real policeman in Musa Qala, the Helmand town recaptured from the Taleban in December, and Koka's fate is something of a test case for Britain's stabilisation efforts in the province.

Koka — real name Abdul Wali Khan — served a 14-month sentence in Bagram jail, north of Kabul, where he was imprisoned by the Americans for suspected insurgent involvement after the Taleban were ousted in 2001.

Released, he reappeared as a militia commander and lawman for the Afghan Government in Musa Qala, where by 2006 his tenure was marked by allegations of human rights abuses, killings and robberies.

“The last time he was here he used to kill people all the time on orders,” Mullah Salaam, Musa Qala's Governor, said yesterday. “And he took $20,000 (£10,000) a day in opium taxes. There were so many people killed in Musa Qala, either by his militia or the Taleban.”

The behaviour of Koka's militia so inflamed tensions that many locals chose to support the Taleban, who later captured the town. After that, there was scant evidence that he might have reformed.

A senior UN official, speaking to The Times on condition of anonymity, cited Koka's direct involvement in an April 2007 massacre of 40 civilians in a Helmand village southwest of Lashkar Gar, where his militia conducted operations against the Taleban.

However, after the recapture of Musa Qala by Nato and government forces eight months ago, rumours of Koka's reappointment as police chief grew. Locals and British officers alike seemed unambiguous in their opposition to the move.

Nevertheless, Koka was reinstated three months ago after pressure from the Interior Ministry and the Afghan Army. His men are with him. Haji Lala, his deputy, estimated that 75 per cent of Koka's 220-strong police force were made up from his 2006 militia.

“They are never going to be Strathclyde Police,” remarked Sergeant Don Wilson, of the 2nd Battalion The Royal Regiment of Scotland, who has been mentoring Koka's police. “But the Taleban are afraid of them. And people respect him. Anything goes wrong and he's the first one there.”

The shadows of history stretch long in Helmand however. “Some people may forget Koka’s actions last time he was here,” another police official said. “Or they may support him because of his new power. But not everyone will forget his behaviour, the killings, robbery and burning of shops, whatever the posters and pictures now.”

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