THE theft of data on 600,000 people, including serving members of the Royal Navy, Royal Marines, and the RAF, was initially kept from the police and ministers, it emerged today.

Although the theft of the laptop that contained the unencrypted data was reported to the police immediately, they said it was only “later” that they were told what was on it.

That raised questions over Ministry of Defence claims that it had held back from releasing details of the data loss on the advice of the police.

Ten days after the computer went missing, senior ministry of defence officials remained uncertain yesterday as to the extent of the data and why it was on the laptop.

They will spend the weekend trying to put together a full picture of what the information was and how it came to be on the laptop ahead of a statement to the Commons by Des Browne, defence secretary, on Monday.

Liam Fox, shadow defence secretary, said that when Browne rang him on Friday it was clear he was not at all sure what the data contained.

“I don't think they know what was on this,” Fox said. “There are a very large number of questions that will have to answered on Monday. This is either catastrophically lax procedure or this individual is very irresponsible.”

The information, which included national insurance, passport and bank account numbers for a number of serving personnel, was stolen from outside a house in the Edgbaston district of Birmingham on the night of January 9 to January10.

The computer did not have anything other than basic security systems, but once the thief had accessed the computer the data itself could be easily read.

The MoD said it was writing to the 3,500 people whose bank accounts were included in the database and informing the banks. But the fact that ten days after the theft the letters had not yet been sent out was further evidence that the extent of the loss had been held back.

The majority of the 600,000 individuals on the database are believed to have been people who inquired about joining the forces and left only their names and contact details.

But it is reported to include the personal details of all those who joined the Royal Navy, the Royal Marines and the RAF in the past decade, raising major security concerns.

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