Image copyright ALAMY

Interpreters who worked with US forces in Afghanistan are being hunted down by the Taliban. Thousands have emigrated to the US but others have been blacklisted, refused a visa, and left in grave danger.

In spring this year, two men rang Nader's doorbell so hard they pushed it half way through the wall of his mud-brick house. He came to the door, they coaxed him outside and then dragged him to the village graveyard.

"When I realised they were taking me somewhere to be executed I started yelling and fighting," he says.

"My brother came out to find me, but by the time he'd come they'd shot me, I just lay down and they left."

If Nader had not struggled he would have been shot in the head. Instead, as the militants hurried to get away, they only managed to shoot him in the leg.

Nader's village, about an hour's drive north of Kabul, is hostile territory for the Taliban. It was home to some of the bloodiest fighting during the Soviet occupation in the 1980s, and the local mujahideen force that protected the area then has remained firmly in control ever since.

Media playback is unsupported on your device Media caption Nader: 'My home has become a combat place'

And yet, the Taliban found Nader even there. So he, like many other former interpreters remaining in Afghanistan, now lives in Kabul.

"We are looking for a chance to save our lives from this and not be more at risk," he says. "The only place I was feeling myself was my own home. Now that place has become a combat place for me."

Thirteen thousand Afghans who worked with the International Security Assistance Force have fled to the US under a special visa programme created especially for them, state department officials say. About 70% of the total are said to be interpreters. But this route to safety has been closed to hundreds of people who, like Nader, were sacked from their jobs and then blacklisted as a security risk.

Image caption Many of the interpreters say they have received death-threat letters from the Taliban

Nader was sacked because he refused to carry out an order to shout at Afghan women.

Others made the mistake of taking a mobile phone on patrol, prohibited because it could have enabled them to alert the Taliban to the soldiers' presence. One accidentally left a pair of US serviceman's trousers in his bag as he went out of the base - a dangerous mistake, because if the trousers fell into the wrong hands they could be used by a militant to disguise himself.

Many of the interpreters in fact did nothing wrong, they just failed a polygraph test.

Interpreters took the tests regularly, and were asked questions designed to weed out Taliban sympathisers. But the interpreters say the system was unreliable. One of them, Sayid, says he failed the test simply because he was nervous. After seven years of service with the US and Canadian forces he was refused entry into his base one day when he returned from leave.

Image caption The photograph shows Sayid, holding a US rifle, alongside a US soldier

It could be argued that some of the men deserved to be sacked - but being on the blacklist is tantamount to a death sentence, they say.

Sayid says that even in Kabul he is not safe.

"If I get caught anywhere in Kabul right now, they kidnap me, they torture me, they, head off - you know - cut my head off."

Media playback is unsupported on your device Media caption Sayid: 'We have been left behind to be executed'

He says he and the other "left-behind interpreters", as they call themselves, were counting on the US to help them, after they worked alongside US soldiers and took the same risks.

"I've been in a lot of missions," he says. "I suffered the hard parts. I continued my work despite threats."

The system in which the interpreters are given a black mark was originally made to track Taliban militants, opium growers and criminals, by recording iris scans and fingerprints. It has since become a database containing the biometric data of anyone who has had contact with coalition forces - and their chances of employment depend on their status within the database.

Being on the blacklist means the interpreters cannot get a job with any foreign military forces, any foreign company, or any branch of the Afghan government, including the army or police.

They will not be allowed on planes, and even claim to have been refused entry into airports.

In effect, most of them are now virtually unemployable, despite in many cases being the only breadwinner in the family.

The state department says the US is "committed to supporting those who - at great personal risk - have helped us". But an official told the BBC that while 9,000 "special immigrant visas" have been issued to Afghans this year, and the programme will be extended to 2015, those interpreters "dismissed for [a] cause will have a really hard time in getting a... visa".

More than 30 "left-behind" interpreters gathered recently in a Kabul park to discuss their future.

Media playback is unsupported on your device Media caption Thomas Martienssen joins a group of "left-behind" interpreters

One, called Khalid, worked with US Special Forces in Helmand province.

"It was harsh, we were in a firefight all day," he says. "I've been shot once, I was taken to a British hospital in Bastion, I've been blown up twice… Sometimes I wake up in the middle of the night and shout. I have been through a lot."

When the Helmand base closed, he took a job with US civilians in Kabul. But when that job came to an end as well he applied to retake the test for interpreters who work with special forces. He was shocked to learn he had been blacklisted.

"I was like, 'What?!' They said: 'You argued with a woman who was a US civilian.'

"I know that woman, I had an argument with her, and she blacklisted me."

Khalid's mother is dead, his father is old and he has four young siblings to feed, but he cannot leave the house without disguise.

"We're in great danger, even coming here today I covered my face," he says.

The Taliban have shown they can already operate in Kabul. As more and more foreign forces leave Afghanistan, the situation of the interpreters will become increasingly desperate.

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