The Ministry of Defence has admitted to losing 28 laptops since the beginning of the year.
Defence minister Bob Ainsworth revealed the figure on Thursday in response to a written parliamentary question by shadow secretary of state for defence Liam Fox.
The laptops were lost between January 1 and 11 May 2009. The Ministry of Defence also admitted to losing 20 flash drives and 4 PCs in the same period.
Ainsworth said that procedures were being put in place to militate against MoD data loss incidents and mitigate error.
"The MoD takes any loss of information and associated media storage devices very seriously and has robust procedures in place to mitigate against such occurrences," said Ainsworth. "New processes, instructions and technological aids are also being implemented to mitigate human errors and raise awareness of every individual in the department."
The Ministry of Defence was unable to confirm at the time of writing how many of the laptops and USB sticks had been encrypted.
In January Des Browne, the secretary of state for defence, admitted that the MoD had lost three unencrypted laptops in 2008, one of which containing the details of up to 600,000 defence personnel. At the time, Browne said that the MoD had "clear systems in place" that "ought to have been respected".