The policing watchdog has called for the BBC and the police force to explain the leak about the raid on Sir Cliff Richard's house.
Chief Constable Alex Marshall, chief executive of the College of Policing, said if the disclosure was unauthorised it would contravene the code of ethics and those responsible should be held to account.
He said: "It is paramount that investigations are conducted fairly, impartially and with integrity.
"The BBC have said that it was not South Yorkshire Police who first alerted them to this investigation and have not confirmed where the information came from.
"If the information was an unauthorised disclosure from within policing then it would be contrary to the Code of Ethics and the person concerned should be held to account.
"The presence of a BBC film crew at the scene of a police search, usually a closely guarded secret, has attracted understandable attention. It is for South Yorkshire Police and the BBC to explain the circumstances of this case."
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