The SNP last night called for a top-level probe into data security across the whole of Whitehall after it emerged that of the 600,000 personal details lost when a UK Government laptop was recently stolen, almost 60,000 were from people in Scotland.

Angus Robertson, the Nationalist leader at Westminster, received the information in a written parliamentary answer from the Ministry of Defence.

It revealed that personal details of 59,553 people in Scotland were lost following the computer theft from a Royal Navy recruiting officer in Birmingham on January 9. Many of the unencrypted details were from those people who had applied to join the armed forces and included passport, national insurance and NHS numbers as well as some banking details.

The breakdown of other people was: 459,778 from England; 37,546 from Wales and 14,223 from Northern Ireland.

"The MoD's response to my questioning brings home the staggering scale of this data loss by the UK Government. In Scotland, the loss is equivalent to more than 1000 people in each constituency," insisted Mr Robertson, the MP for Moray.

"The data loss included passport information, national insurance numbers, driver licence information, family details, NHS numbers, and thousands of banking details. Much of this data is important to devolved governance and policing arrangements and the MoD needs to co-operate fully with administrations in Edinburgh, Cardiff and Belfast."

Mr Robertson said that the obvious and immediate concern must be the security of individuals and their families, whose data was stolen.

"But we also urgently need assurances from the MoD that operational security has not been compromised by this grave breach," said the SNP MP."It is unfathomable that the MoD could let this happen and we must now have a top-level investigation into data security right across UK government departments."

Last week, Des Browne, the Defence Secretary, revealed that the investigation into the loss of the laptop had uncovered two similar thefts since 2005.

He told MPs that the two laptops held similar data to one stolen from the recruiting officer in Birmingham but on fewer people.