The Government’s reputation for data security was dealt another blow yesterday when the Ministry of Defence admitted that many more laptops and USB memory sticks had gone missing than previously reported.

Officials admitted that 658 MoD laptops had been stolen over the past four years – nearly double the figure previously claimed. A further 89 were “lost”, with just 32 recovered. They also said that more than 26 memory sticks containing classified information had been stolen or misplaced since January.

The Lib Dems condemned the latest security breaches, which happened despite a cross-Whitehall drive to tighten procedures, as evidence of “shocking incompetence”. The embarrassing new details were disclosed by ministers in response to questions tabled in Parliament. Previously the MoD had admitted to 347 laptops being stolen. Defence Secretary Des Browne was forced to issue revised figures after “anomalies in the reporting process” were discovered.

In a separate response, ministers said that 121 of the department’s USB memory sticks had been taken or misplaced since 2004, of which 26 went missing this year, including three that contained information classified as secret and 19 that were restricted.

Lib Dem frontbencher Sarah Teather said: “It seems that this Government simply cannot be trusted with keeping sensitive information safe. It is frightening to think that secret MoD information can be lost or stolen. How can they expect us to trust them to keep our personal information safe in their unnecessary and expensive ID card scheme?”

Last month the MoD was heavily criticised by a review of its data procedures which warned that basic security discipline had been forgotten and there was “little awareness” of the danger of losing information.

An MoD spokeswoman said: “Any loss of data is investigated fully. The recent report on data losses by Sir Edmund Burton found that MoD policies and procedures are generally fit for purpose, but also identified a number of areas where MoD needs to do better in protecting personal data. MoD has developed, and is now working through, an action plan to address all of the report’s recommendations and bring the department’s handling of personal data to an acceptable state.”

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