Laptops containing sensitive information may no longer be reomoved from any public sector offices.
Sir Gus O’Donnell, cabinet secretary, e-mailed civil servants to declare the ban.
The move follows the theft of a laptop last week from the car of a Royal Navy recruitment officer in Birmingham.
The laptop, stolen on 9 January, contained sensitive details about 600,000 prospective military recruits, including details of religions and some banking records, and was not encrypted.
Des Browne, British defence secretary, admitted in the House of Commons yesterday that internal investigations had established that two further laptops with similar data had also been stolen earlier.
“It is not clear to me why recruiting officers routinely carry with them information on such a large number of people or, indeed, why the database retains this information at all,” Brown said.
Letters have been sent to all 3,700 whose bank details were included in the database, and have also been sent to the 153,000 people who applied to join the Royal Navy, the Royal Marines or the Royal Air Force during the relevant periods. Details such as passport and National Insurance numbers were included in the stolen data.
Browne told Parliament that he has appointed a senior dedicated data protection officer to ensure MoD practices and procedures are upheld.