Users of the Guardian's jobs website have been warned about the threat of ID fraud after criminals hacked into the newspaper's systems.

The newspaper has emailed users to warn them about the danger after the "sophisticated and deliberate hack".

Users' data surrounding the job applications have been accessed, and they are being advised to inform their banks, building societies and creditors, so they can monitor their accounts.

Those affected should also obtain a copy of their credit record from one of the three main credit reference agencies; Callcredit, Equifax or Experian.

The Guardian is also advising those who think they have become the victim of identity fraud to contact the fraud prevention service CIFAS to have notice on their credit file indicating that their name and address may be used to perpetrate identity fraud.

An investigation into the hack is being carried out by the central e-crime unit at New Scotland Yard.

The Guardian claims on its website that its "system is now secure".

"The police remain anxious to keep information about the apparent theft to a minimum, in order not to compromise their investigations, but did agree with us that we could inform those users who may be affected," the newspaper added.