DORSET police is warning the public to take steps to ensure that their bank and building society accounts are not plundered by criminals.

The warning comes after a survey showed that one in ten people are putting themselves at risk of credit or debit card fraud by writing down their Pin or sharing it with someone else.

Consumer group Which? said an estimated four million debit card holders and three million credit and charge card holders were unwittingly putting themselves at risk of having their accounts emptied by criminals.

A third of those quizzed admitted having written down their Pin and keeping it in their wallet or handbag. A further 36 per cent had it written down somewhere at home while nine per cent made a note of it in their office.

The majority of those questioned thought they would have any money they lost refunded if they were victims of credit or debit card crime.

But, while banks and card providers will not automatically refuse to pay out if a card is stolen and the Pin is used, they may not pay compensation if they can prove that the holder had not kept their details secure.

Martyn Saville, Which? credit card expert, said: “The results show that too many consumers are putting their finances in jeopardy by not taking simple precautions.

“Writing down your Pin is like leaving your door open when you leave the house.”

A Dorset police spokesman said: “The public are advised that they should never give their Pin to anyone over the phone, even if the caller says they are from a bank or building society.

“Legitimate callers never ask for Pins. Avoid writing down your pin and storing it anywhere, particularly with the accompanying card.”

He added: “If you find your Pin hard to remember try changing it to something more memorable but still not easily associated with you.”

• Which? questioned 1,045 people during March.