The Ministry of Defence has admitted losing 440 IT devices in the last year, including computers, hard drives and memory sticks.
Some 217 laptops were reported lost or stolen from a range of MoD sites in 2008. Ninety six memory sticks, 80 hard drives and 47 desktop PCs also went missing, the MoD said.
Bob Ainsworth, defence minister, told MPs in a written parliamentary answer that the RAF lost 104 laptops last year, while the army lost 38 laptops, 37 desktops, 37 hard drives and 37 USB sticks. A total of 1,649 such devices were lost across the MoD in the last six years.
In spite of a crack down on security, last year was the worst year for hardware loss in the period. Nearly three times as many hardware devices were lost last year compared to 2007, when 156 devices were lost.
An MoD spokesperson said the department was making "good progress" on security. "We have already encrypted 20,000 laptops that were not previously protected to the level required by current MoD and government policy," the spokesperson added. "We issue sensible common sense rules to protect sensitive information and MoD property."
In October last year, the MoD admitted that an unencrypted hard drive, which had been lost by contractor EDS, may have contained sensitive details of 1.7 million armed forces personnel and potential recruits. At the time, Ainsworth told MPs that it was not necessary for the drive to be encrypted "because it was stored within a secure site that exceeded the standards necessary for restricted information".
In September, the MoD made similar claims that encryption was not necessary in highly secure sites, even though three portable USB hard drives containing sensitive information had been stolen from "secure" parts of the RAF Innsworth base in Gloucestershire.
And a laptop was stolen from an officer in the navy at the start of the year, containing the details of 600,000 new and potential recruits to the Navy and Army. In the summer, a report by Sir Edmund Burton said the loss showed that the MoD was "not treating information, knowledge and data as key operational and business assets".