London, Oct 10 (IANS) In the latest incident of security breach in Britain, a computer drive containing information about a large number of British armed forces personnel is missing, the Ministry of Defence said Friday, The Independent daily reported.The portable drive contains personal details of about 100,000 serving officers of the army, navy and air force, and their relatives.

The ministry said the theft came to their knowledge Wednesday and MoD police were investigating.

In July, the ministry admitted that 26 portable memory sticks containing classified information were untraceable. More than 600 laptops containing classified information went missing over the past four years.

Liberal Democrat shadow defence secretary Nick Harvey said: “This is an extremely serious news and the immediate priority must be to ensure the security of all military personnel”.

Harvey also demanded an urgent investigation into the “disturbing” breach of security.