The secret plans are in the back of a taxi

Britain's first line of national security, the Ministry of Defence (MoD), has lost almost 600 laptop PCs over the past five years.

According to written answers from the Home Office given to Liberal Democrat MP Paul Burstow, 1,354 laptops have been reported missing from government departments since 1996.

The MoD has lost 594 computers alone, with the Department for Work and Pensions mislaying another 419.

The MoD's network had been infiltrated 27 times by hackers since 1999.

Government laptop losses last stirred the nation's interest in 2000 when John Speller, then armed forces minister had his laptop stolen during a home robbery.

In the same year, an M16 officer left his computer in a taxi after a night out in Vauxhall, London.