The credit card details of 19,000 Brits have been found on a cached Google page, where they had been accidentally published by fraudsters.
The numbers, expiry dates, names and addresses of British Visa, MasterCard and American Express cardholders were recently founded in the search engine's Web cache.
The data was originally posted on a server in Vietnam linked to a Web site used by fraudsters. The site was closed down in February but the information remained available on a cached page for some time before being removed by Google.
Payments association Apacs says most of the affected cards have now been cancelled but it is not clear if all cardholders have been informed that their details were published.