The Bishop of Rochester, the Rt Rev Dr Michael Nazir-Ali, has warned that a campaign by Muslim extremists in Britain to intimidate and attack converts to Christianity risks ending in murder.

The Bishop was highlighting the extent of persecution experienced by Christian converts from Islam during Channel 4's 'Dispatches' programme due for broadcast tonight. He added that it was just a matter of time until an "honour killing" took place.

"We have seen honour killings have happened and there is no reason why this kind of thing cannot happen, he said.

Bishop Nazir-Ali said that the blame lay with Muslim leaders for not offering clear enough teachings to their followers about the importance of religious freedom in Britain.

The Barnabas Fund, a charity highlighting Christian persecution across the world, has estimated that there are more than a thousand attacks each year in Britain committed against former Muslims who have converted to Christianity.

Bishop Nazir-Ali said: "It's not for me to put words into their mouths [Muslim leaders], but I would look to them to uphold basic civil liberties, including the right for people to believe what they wish to believe and even to change their beliefs if they wish to do so."

According to The Barnabas Fund, persecution can take place in the form of verbal abuse and being spat at, but can also escalate to converts being seriously assaulted by gangs of Muslim men.

It is also believed by the persecution watchdog that some women converts have been abducted and forcibly taken to Pakistan.

Tonight's Dispatches programme will also tell the story of one convert, Nissar Hussein, a hospital nurse from Bradford. Hussein converted to Christianity ten years ago following the death of his younger brother, and he later evangelised and converted his wife.

However, over the past decade his family, including their five children have experienced almost daily abuse and even violence from local Muslims in Bradford.

Windows have been smashed at their home, people have vandalised their property by writing "Christian dog" on their front gate, and their children have even been sworn at and spat at on their way home from school. Hatred has escalated to the extent that the family has received death threats.

Hussein says: "They told me categorically had I been in an Islamic country, ie Pakistan, the Middle East, that they would actually be the first to chop off my head."

The Hussein family eventually moved out of their home after six years, after fearing they would be killed.

The Barnabas Fund has produced research indicating that there are approximately 3,000 Muslim converts to Christianity in Britain. About 2,000 of them are Iranians, while the rest are from the Indian subcontinent and Afghanistan.

Patrick Sookhdeo, director of the Barnabas Fund, said: "I think the situation is worsening in the UK because we are moving towards parallel communities - I don't like to use the word ghettoisation. Muslims feel abandoning their religion is like a betrayal."