A WAR of words broke out last night over who was responsible after yet another investigation into Cleveland Police collapsed.

Operation Dollar was set up to examine allegations made by zero tolerance pioneer Detective Superintendent Ray Mallon after he was suspended three-and-a-half years ago.

The inquiry was carried out by a team of officers drawn from three other forces and cost more than £326,000 in taxpayers' money.

Detectives examined allegations of assault, conspiracy to pervert the course of justice, falsehood, neglect of duty, improper disclosure of information, improper treatment of witnesses, incivility and discreditable conduct.

Most of the claims were levelled against three officers - a detective superintendent, a detective inspector and an inspector who has since retired.

Despite the wide-ranging number of complaints, the Police Complaints Authority announced last night that the team had found "insufficient evidence to justify formal disciplinary proceedings" against two of the officers.

The PCA said the inquiry had found evidence of incivility by a detective inspector. His punishment amounted to "strong advice" from the Assistant Chief Constable.

After thousands of man-hours and a huge amount of public money, Operation Dollar ended with an officer receiving a dressing-down from a senior officer.

The end of Operation Dollar comes just weeks after Operation Lancet - one of Britain's longest and most costly police corruption investigations - ended with no criminal charges.

And last night, an unseemly public row began over who was responsible.

Chairman of Cleveland Police Authority Councillor Ken Walker laid the blame for the inquiry squarely on Det Supt Mallon.

He said: "I think it is important to underline that the time and cost of Operation Dollar arose directly out of the allegations made by a detective superintendent - and the investigation has concluded that, in the case of two officers, there should be no action, either criminal or disciplinary.

"A great deal of concern has been expressed, quite rightly, about the time and cost involved in Operation Lancet and subsequent investigations such as Operation Dollar.

"It is important to recognise that in the case of Operation Dollar, the allegations were made by an individual officer."

Cleveland Police said the Dollar statements, amounting to 200,000 words, had "resulted in a lengthy inquiry, costing £326,400, delaying the original Operation Lancet investigation".

The allegations were angrily dismissed by Det Supt Mallon, who remains suspended, despite being cleared of criminal wrong-doing, pending a disciplinary hearing.

He said the allegations he had made helped clear him of any criminal charges.

Det Supt Mallon said: "The Dollar investigation was set up as part of the Lancet inquiry following the decision of Cleveland Police to suspend me from duty and accuse me of behaviour that could be construed as criminal.

"One of my statements also raised very serious concerns about the management and control of the Lancet investigation by senior members of Cleveland Police and the Police Complaints Authority.

"It would appear these concerns are shared by Home Secretary Jack Straw, who has asked a retired chief constable, Sir John Hoddinott, to review the way this costly inquiry has been run."

Ashok Kumar, MP for Middlesbrough South and East Cleveland, said: "It seems when people stand up for their civil and humans rights they are treated in a disdainful way by the arrogance of those who hold senior position.