Shoppers are being told to look after their till receipts from certain Morrisons supermarkets or risk becoming the victim of credit card fraud.
The Association for Payment and Clearing Services (APACS) has warned that bank card numbers - which are printed on the receipts of the Bradford chain - could be used to remove funds from customers' accounts.
Richard Tyson-Davies, spokesman for the group which leads the fight against credit card fraud, called on Morrisons to adopt a new system to block out some of the digits as a safeguard against crime.
"We are encouraging businesses to stop the practice of printing these details but we cannot force them," he said.
"We would advise customers to dispose carefully of their receipts because these numbers can be used to make purchases."
He added that although banks would foot the bill for illegal money transfers, it could cause "major hassle" to the customer.
Morrisons supermarket at Thornton Road in Girlington is currently the company's only store in Bradford to operate the safety system, which is known as truncation.
But a spokesman for the chain said it would be introduced in all other stores "as soon as was practicably possible".
Morrisons customer John Kay discovered another shopper's receipt among his groceries after visiting their store in Thornbury.
It featured a 16 digit bank card number and expiry date.
Mr Kay, 57, of Keswick Street, Tyersal, said: "Most people just throw these things away not realising that anyone could just pick them up and try to empty their bank accounts. I couldn't believe that supermarkets are still printing such information in this day and age. You hear of plastic fraud going on all the time."
According to APACS, around 50 per cent of businesses now use truncation.
These include major chains such as Marks and Spencer, Tesco and Sainsbury's, who have all introduced the systems to protect customers against fraud.
A spokesman for Marks and Spencer said: "If customers drop a receipt with credit card numbers on it, someone could just pick it up and use it to order goods over the phone."
Greg Sage, a spokesman for Tesco, added: "We believe it is important for security reasons not to print bank details on till receipts."
e-mail: gareth.tidman
@bradford.newsquest.co.uk
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