CITY MPs and ex-servicemen have demanded answers after the latest lost disk blunder.

The calls came as the Ministry of Defence (MoD) yesterday revealed that a lost computer hard drive may contain the personal details of as many as 1.7million people who have inquired about joining the armed forces.

When the loss of the disk from Hampshire-based contractor EDS was first announced last week, it was thought it contained the names, addresses, passport numbers, dates of birth, next-of-kin and driving licence details of up to 100,000 Army, Royal Navy and RAF personnel.

But yesterday afternoon Armed Forces Minister Bob Ainsworth revealed it contained data relating to large numbers of people who asked for information about careers in the forces.

Mr Ainsworth said the incident "illustrates the need continually to review and enhance our arrangements for personal data".

He also announced the launch of an investigation by the MoD Police and a helpline for those who may have been affected by the loss on October 8.

The move comes after the theft of a military laptop earlier this year which contained personal information on 600,000 people – most of whom had either expressed an interest in joining or had actually joined the forces.

Today city politicians and veterans demanded immediate action.

Linda Gilroy, MP for Plymouth Sutton and a member of the influential Defence Select Committee, said: "Clearly Bob Ainsworth's statement reflects the crucial need for improvement. That is an understatement as far as I am concerned. This sort of information should be treasured and guarded against this sort of thing. I will have a number of opportunities to question ministers and other people and I will not lose any opportunity to do just that."

Alison Seabeck, MP for Plymouth Devonport, said: "It is deeply shocking. It seems extraordinary that despite everything that has happened we are still losing personal data and information.

"It is unacceptable that Government partners lose these details."

South West Devon MP, Gary Streeter, added: "It is completely unacceptable. These incidents are happening far too often and the Government needs to get a grip. Senior people in this Government department need to be held to account."

Roger Garratt, a former navy Lieutenant Commander and secretary of the Crownhill branch of the Royal British Legion, said: "It beggars belief. It is not what you expect of a security conscious organisation."

A retired Plymouth-based Royal Marine Commanding Officer – who asked not to be named, added: "If someone in the military had lost this hard drive they would be dragged over the coals and court-martialled.

"It is an added worry for service personnel and their families, and indeed people who look at signing up.

"The worrying thing is that when the Government loses these details we do not know who finds them."

Where people simply made casual enquiries, only their name and contact numbers are likely to have been recorded, said Mr Ainsworth.

But for those who went on to apply to join up, the drive could include more extensive data, including next of kin details, passport and National Insurance numbers, drivers' licence and bank details and NHS numbers.

It is also unlikely the details on the hard drive were encrypted for security.