ZERO Tolerance detective Ray Mallon was finally "free" of Cleveland Police last night but the bitterness and recriminations are far from over.

A Press conference staged by Mr Mallon today will ensure that the wrangle which has blighted Cleveland Police for four-and-a-half years will get even dirtier.

And his accusers will get their chance to publicly condemn him as a guilty man when the Cleveland Police Authority finally opens its doors to debate Operation Lancet tomorrow.

It is sure to be an increasingly bloody battle as Mr Mallon launches his campaign in earnest to be mayor of Middlesbrough and his opponents go all out to stop him.

Yesterday, Mr Mallon was "required to resign" from the embattled force following his sensational about-turn last week when he decided to plead guilty to the 14 disciplinary charges against him.

His decision terminated the hearing which would have been adjourned until July, preventing him from pursuing his dream of becoming Middlesbrough's first directly-elected mayor in May.

He said last night: "When I was told there was a requirement for me to resign, I felt as though the shackles were just loosening on my ankles. I feel much happier in myself now because I am free."

Mr Mallon said he had made Cleveland Police "an offer they couldn't refuse.", and in return was allowed to resign rather than be sacked, meaning he walks away from his 28-year career with a full pension.

Last night, the Police Complaints Authority which has overseen Operation Lancet and which was unable to collect enough evidence against Mr Mallon to press criminal charges, launched a scathing attack on the officer nicknamed Robocop.

PCA deputy chair Ian Bynoe accused him of "dereliction in duty" by failing in 1997 to investigate reports that one of his officers was supplying drugs to prisoners in custody and tipping suspects off about planned police action.

Mr Bynoe blamed Mr Mallon for causing Lancet to drag on so long, and said his behaviour was "wholly incompatible with the standards required of even the most junior of police staff".

But Mr Mallon said: "I consider my name was cleared in June 2000 when I was cleared of crime.

"The disciplinary inquiry has been nothing more than a witchhunt. I do not feel this outcome affects my reputation.

"I am confident that had I been allowed legal representation, I would have been cleared of all charges but I was totally focused on my aim of standing as mayor. The people of Middlesbrough will be my judge and jury in May."

Middlesbrough MP Stuart Bell urged Mr Mallon to think again about standing for election. He said: "If he had pleaded guilty four years ago, his legacy would have been of a cop who tried to get to terms with our crime. Now it is a reputation that is sullied, a sad day for him and it is a sad day for the police force."

Ken Walker, the chairman of Cleveland Police Authority and Labour leader of Middlesbrough council, urged the 46-year-old "to examine his conscience and consider whether he is a proper and decent person to hold such a high public office".

He promised the public would be given all the information about Lancet at the authority's special open meeting tomorrow.

But as the various parties in Cleveland became more deeply entrenched, Mr Mallon's union, the Police Superintendents' Association, accused the police force of making Mr Mallon a scapegoat.

Chief Superintendent Philip Aspey, Deputy Secretary of the association, said: "The force has used chequebook discipline here and calculated delaying tactics and we are appalled that these tactics have been deployed in such a way against an individual officer."

Other interested parties urged the Home Secretary to agree to The Northern Echo's call for an independent inquiry into the fiasco of Lancet.

Councillor David Walsh, leader of Redcar and Cleveland Borough Council, said: "We think all the issues should be looked at by a Home Office review because of the money and time it has taken.