Rebuke for MI5 over bugging

The intelligence and security services are making an "unacceptably high" number of mistakes bugging the wrong people, an official report has found.

Fresh from their humiliation at the hands of Lord Butler, Britain's spies have been given a telling off for tapping the phones of innocent citizens.

On one occasion they eavesdropped on a serving police officer after his mobile phone number was mistakenly included on a warrant.

Sir Swinton Thomas, the communications commissioner, recorded 39 blunders in his annual report on police and intelligence service snooping.

Most were simple typing errors resulting in David Blunkett, the Home Secretary, authorising the tapping of the wrong phone number.

MI5 made the most mistakes and the security service has promised to tighten its procedures.