Cleveland Police Operation Sacristy probe bill tops £4m 22 May 2013 Last updated at 08:01 Investigations into alleged corruption at Cleveland Police have now cost more than £4m, the BBC has learned. The bill for criminal inquiry Operation Sacristy and separate disciplinary hearings has reached £4.3m, three years after allegations were first made. Chief Constable Jacqui Cheer said the case was "very complex" and the Crown Prosecution Service would consider the evidence and charges in September. Ten people have been arrested and nine remain on bail. Stockton South MP James Wharton said the investigation had brought an "unwelcome additional cost." Cost concerns 'inevitable' "This is a huge amount of public money which is being spent on a very long-running investigation that must have a disruptive effect at the top of Cleveland Police," he said. I've seen investigations into serious organised criminal gangs dealt with far quicker and, in my view, far more professionally than this End Quote Derek Bonnard Sacked deputy chief constable It's got to be a concern that over £4m has been spent, particularly at a time when there isn't a lot of money around. Mrs Cheer said Operation Sacristy was not being paid for out of the force's policing budget - the bill for the inquiry has reached £3.8m and the misconduct probe costs amount to £500k. "It obviously is being paid for by the taxpayer because all money that comes into policing comes from a tax base," she said. The seriousness and complexity of the case that is being investigated was recognised by the Home Office and they are helping us with the cost of that. We always said when we started it that we would go where the evidence takes us. It's a very complex case, it involves a lot of people and it involves a lot of sifting through information. Like an octopus The force's former deputy chief constable Derek Bonnard, who was sacked for gross misconduct, said the investigation had become "like an octopus across the whole organisation and beyond." "I've seen investigations into serious organised criminal gangs dealt with far quicker and, in my view, far more professionally than this," he said. Warwickshire Police started the criminal investigation in May 2011 into "people with current or past associations" with Cleveland Police Authority. The force said delays had been caused by matters out of its control, including the misconduct proceedings which led to the sacking of Mr Bonnard and the force's former chief constable Sean Price.