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Operation Safeguard is an arrangement between the National Offender Management Service and the Association of Chief Police Officers. The estimated cost to NOMS of the provision of police cells under Operation Safeguard in 2007-08 is in the region of £53 million. This includes staff costs. The number of police officers who have taken part in Operation Safeguard is an operational matter for police authorities and chief officers and the information is not held centrally.