The government's ability to keep data safe has gone from a little amusing, to embarassing to downright ridiculous.

And perhaps dangerous with this latest leak.

The Home Office has admitted that an unencrypted memory stick has gone missing, containing details of all 84,000 prisoners in England and Wales.

The information contained included the home addresses of some of the UK's most prolific and serious offenders, as well as some release dates.

The admittal by the Home Office has immediately been damned by the opposition.

The Conservatives say that taxpayers will be "absolutely outraged" and have also demanded that Jacqui Smith, the Home Secretary, releases a statement on how this has happened.

Dominic Grieve, the shadow Home Secretary, said he was "absolutely horrified" by the breach while the Liberal Democrat leader Nick Clegg said: "Charlie Chaplin could do a better job of running the Home Office than this Labour Government."

But Grieve also raised the point that the Gov, and therefore the taxpayer, could not face forking out millions of pounds in compensation to criminals worried about their safety as a result of the data leak.

Grieve said: "The Home Office is entrusted with a great deal of highly confidential material and it seems to be entirely incapable of keeping it secure. And the consequences are very serious. They're serious because it may lead to the identity of the people involved being revealed".

"One of the possible consequences is that criminals will bring legal actions against the government and the taxpayer will then have to pay damages to people, who appear to be pretty undeserving, because of the government's incompetence."

A Home Office spokesman told The Daily Telegraph that the memory stick was lost by PA Consulting, a private company they employed to track and analyse serious and prolific offenders in the "JTrack" programme.

The Home Office claims that it sent the personal details on the criminals to the company in a secure encrypted email, which was then transferred in an unencrypted form on to the memory stick, which was then lost.

The newspaper adds that the transfer of any further data to PA Consulting has been suspended pending an investigation.