Police are re-issuing a warning in the lead up to Christmas about a scam in which a fraudster pretends to be a police officer.

Officers believe fraudsters target elderly people by calling landlines late at night or very early in the morning when the victim is in bed.

The warning comes after two people reported receiving such phone calls in the Cambridge area last night.

In the scam, the caller claims a criminal has been arrested with a substantial sum of money on them and a list of names and addresses, including the victim’s.

The phoney officer then advises the victim to call their bank using a number on the back of their bank card, or the police on 101. The victim hangs up but the caller does not and the call is not terminated.

As a result and without realising it, the victim starts talking to the fraudster again, thinking they have called their bank.

Following a conversation, the offender claims he will need to examine the victim’s bank card and will also need their PIN number as it might be compromised.

The caller says he will send a courier to collect the card before a smartly dressed man arrives at the victim’s home. The card is then taken and the PIN number used to withdraw cash.

Detective Sergeant Adi Bowman said: “Both victims didn’t realise it was a scam until it was too late and there may still be people out there who are unwittingly giving out their bank details.

“Banks will never ask for your PIN number over the phone and you should never give it out. If you’re in doubt about anyone you are speaking to on the phone, hang up and ensure the line has been terminated before ringing back on an official number. You should never give any bank cards to anyone at your door, even if they say they are from your bank.”

To report an incident of fraud, call Action Fraud on 0300 1232040.