Three serving police officers and a fourth man working for the Police Federation were arrested over a suspected £1m fraud on Friday.
Surrey Police arrested two men in their 50s and two in their 40s after the professional body that represents rank-and-file officers alerted detectives of a transfer to a charitable account in August.
The money had been held in accounts by the Police Federation’s constables’ central committee.
The professional body, which represents 122,000 officers, alerted detectives from Surrey Police this week. Specialist officers from Surrey’s economic crimes team are carrying out the investigation.
Karen Mizzi, the detective superintendent in charge of the case, said it would be raised with the police watchdog, the Independent Police Complaints Commission, and the Charity Commission as part of the investigation. All four men will be held in custody while police continue their investigation.
“As the allegation was only reported to us on Wednesday, 16 March, our enquiries are at an early stage but specialist officers, including our economic crime unit, are investigating to establish whether any offences have occurred,” she said.
The Police Federation said it is “co-operating fully with the inquiry and gives Surrey Police its utmost support”. It said the probe would have no effect on the day-to-day running of the federation but provided no comment on the arrests.
A report into police corruption by HM Inspectorate of Constabulary said that “around half of forces do not have the capability to actively seek out and develop intelligence on corruption”. It found that only just over half of the officers and staff surveyed said they trusted the confidentiality of internal reporting systems.
It said there were 3,000 investigations into corruption offences in 2014 leading to about 900 police officers or staff facing disciplinary action.
The Police Federation reported the case to the Surrey force as its headquarters are in Leatherhead. The arrested officers are not members of the Surrey Police force.
The news comes on the same day that Will Riches stepped down as vice-chairman of the Police Federation. A spokesperson for the federation said that he will remain a member of its interim national board.
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