The Ministry of Defence admitted yesterday that 217 of its laptops, 47 desk-top computers, 80 hard drives and 96 memory sticks were lost or stolen during 2008, despite a high-profile security crackdown launched last summer.

The Ministry of Defence admitted yesterday that 217 of its laptops, 47 desk-top computers, 80 hard drives and 96 memory sticks were lost or stolen during 2008, despite a high-profile security crackdown launched last summer.

The latest figures mean more than 1640 of the department's computers and other information devices have gone missing in the past five years.

Although new rules on computer security were hurriedly put in place last summer, 2008 saw the highest number of missing desktop computers, hard drives and memory sticks since 2003. Hard drives with private information about almost half of serving armed forces personnel - including bank and driving licence details, passport numbers, addresses, dates of birth and telephone numbers - are among those which have not been recovered.

The devices contained the details of around 100,000 serving personnel across the Army, Royal Navy and RAF, plus those of their next-of-kin. One also had data on 600,000 potential services applicants and the names of their referees, leading to fears terrorists could exploit the information if the drive fell into their hands.

Everyone known to be on the hard drives were also alerted to watch for possible credit or identity theft. A Cabinet Office spokesman said: "The Cabinet secretary's review of data handling, published at the end of June last year, put in place mandatory safeguards to make our information assurance as robust as possible and improve transparency.

"Departments are taking intensive action to improve data security, including extra training for hundreds of thousands of staff, and the problems reported in recently published resource accounts were made public as a result of this new approach."

An MoD spokesman said the department had now made data security a "top priority". He added: "We have already encrypted 20,000 laptops that were not previously protected to the level required by current MoD and government policy."

In July last year, the government said 747 laptops had been stolen or lost from the MoD in the last four years and only 32 had been recovered.

An unencrypted Royal Navy laptop was stolen from a car in Manchester in October 2006 and an Army laptop that also lacked basic security protection was stolen from a careers office in Edinburgh in December 2005. Army Land Command reported the loss or theft of 38 laptops, 37 desktop computers, 37 hard disk drives and 39 memory sticks.