By Sally Chidzoy
Home affairs correspondent, BBC East
Whitemoor Prison has a high number of Muslim inmates
A former British National Party activist who converted to Islam in jail is trying to radicalise young prisoners, the BBC has learned.
Inmate Stephen Jones is being held in a segregation unit at Whitemoor Prison, Cambridgeshire, the BBC has been told.
The convicted murderer was put there after being suspected of recruiting for groups allied to al-Qaeda.
The case has raised concerns that some radical Muslims are using prisons as a recruiting ground.
The BBC has been told that Jones, who is serving a life sentence, has been held in segregation at Whitemoor for about three weeks with two other Muslim prisoners.
Sources have told the BBC he was caught attempting to radicalise a number of fellow inmates after he himself converted to Islam.
The BBC understands that intelligence sources believe that he is being paid by an al-Qaeda-influenced group.
It is thought to be the first time that an inmate has been punished by being held in segregation for activities of this kind.
When Whitemoor Prison opened in 1992, 14% of its prisoners were Muslim, now the figure is about 30%, the BBC has learnt.
Steve Gough, vice-chairman of the Prison Officers Association (POA), said the organisation had been worried about the situation for a number of years.
"This shows what we've been saying. If you can get someone that's so right wing converted then a normal prisoner is going to have absolutely no chance," he said.
"Those people come inside and they're dealt with as normal prisoners, kept on normal locations and they can radicalise."
The POA believes extremist Muslim prisoners should be kept apart from mainstream inmates who are often vulnerable to exploitation.
Youth worker Sulaiyman Matthews, an orthodox Muslim who is working against extremism, said he had talked to prisoners on their release and many of them were angry and had been radicalised.
Mr Matthews said the British public needed to know the "potential threat".
The government said it was working to improve its awareness and understanding of extremism and radicalisation to maximise public protection.
Stephen Jones, who is in Whitemoor Prison, is considered disruptive and dangerous