A former member of the British National Party has told of his 'nightmare' 14-year battle to prove that he was recruited to work as an informant for West Yorkshire Police.
Gary Shopland, 55, spent seven years with the right-wing party while living in Huddersfield, from 1996-2003, becoming a close associate of party leader Nick Griffin.
The party was one of the most controversial movements in British politics, and faced accusations of exploiting racial tensions following riots in Bradford and Oldham in 2001.
But Mr Shopland claims he only joined the BNP after being approached to work for the West Yorkshire force.
He said: "I've never been a racist, never been involved in far right politics. The police recruited me off the street, put me inside the British National Party ... let me get on with it and now I'm in a position where they've turned their back on me and betrayed me."
Before joining the BNP Mr Shopland was well known locally for his exploits as an ultra distance runner.
He says he was on a training exercise in Snowdon with a police officer friend when the possibility of becoming an informant was discussed.
Having become a party member, Mr Shopland attended party meetings, made notes about their activities and recorded phone calls with fellow activists.
He claims payments from police were always off the books.
"They'd pay me in brown envelopes at the back of the car, in some supermarket car park high up in the North Yorkshire Moors," he said.
After seven years with the BNP, Mr Shopland says things turned sour when a national newspaper published an article referring to his membership of the party.
"It was the beginning of a nightmare," he said. "People that used to be my friends to chat to suddenly wasn't, I started losing jobs, I'd been there for a while - people not going to go in there because you're a Nazi."
For the last 14 years Mr Shopland has fought unsuccessfully to force West Yorkshire Police to corroborate his story.
While the force will neither confirm nor deny that he worked for them, they have written a letter appearing to support his claims that he never held far right views – saying reports to the contrary are "totally inaccurate and without proper foundation".
In a separate letter, the West Yorkshire Police and Crime Commissioner says that while he supports the force's stance, Mr Shopland's claims raise a serious issue about how police exercise a duty of care towards what he calls "covert human intelligence sources" and "what measures are in place for their recruitment and monitoring".
But Mr Shopland says his life has been ruined because of the refusal to confirm his claims.