Ray Mallon last night turned to Home Secretary David Blunkett in a bid to prevent his mayoral campaign from being derailed.

The man dubbed Robocop fired off a letter of complaint to Mr Blunkett over the behaviour of his accusers at Cleveland police.

Mr Mallon, via his solicitors, urges the Home Secretary to step in and allow a "fair and proper" election without undue influence.

The letter, seen by The Northern Echo, accuses Chief Constable Barry Shaw of personally abusing Mr Mallon in his controversial "empire of evil" speech.

Both Mr Shaw and Councillor Ken Walker, chairman of the Cleveland Police Authority, are said to have presented "selective and misleading" information to the public intended for confidential disciplinary proceedings.

Mr Mallon accuses the Chief Constable of entering political debate in partisan terms to the advantage of the Middlesbrough Labour party, of which Coun Walker is the leader.

The letter mentions the recent leak to The Observer newspaper which was granted access to hundreds of pages compiled by investigators working on the Operation Lancet anti-corruption probe.

It adds: "He Ray Mallon is concerned that if the present situation is allowed to continue unchecked his campaign to be Mayor of Middlesbrough will be jeopardised by unlawful, selective and unfair criticism of his character."

Mr Blunkett has already received Cleveland police's version of events surrounding Lancet and the disciplinary proceedings against Mr Mallon.

It is seeking a meeting with the Home Secretary, who has been under pressure to call an inquiry into the whole affair.

Operation Lancet found no evidence of criminal wrong-doing by former Superintendent Mallon.

He still faced 14 internal disciplinary charges and claims he was forced to enter guilty pleas in order to be free of Cleveland police in time to run for mayor.

Mr Mallon has pledged that his name will be among the nominations when they open on March 25.

Last night the Home Office said they were awaiting receipt of Mr Mallon's complaint letter and would comment in due course.