In the latest data breach to hit the headlines, Radisson Hotels & Resorts says its computer systems have been illegally accessed, putting customer card details at risk.
In an open letter on its Web site, the chain says some of its hotels in the US and Canada are affected by the breach, which happened between November 2008 and May.
Names on credit and debit cards, as well as numbers and expiration dates are exposed but not social security numbers. Radisson says it does not know how many people have had their data exposed.
"We recommend that you review your account statements and credit reports closely. To the extent there is any suspected unauthorized card activity, it should be reported to the bank that issued your credit card," says the letter.
The firm says it was made aware of the breach by Visa, MasterCard and payment processors and is now working with law enforcement and forensic investigators.
A review of the affected computer systems is underway and additional security measures designed to prevent a recurrence of such an attack have been implemented.
Earlier this week prosecutors charged a Miami man with hacking into the computer networks of several firms - including Heartland Payment Systems, 7-Eleven and Hannaford Brothers - and stealing the details of 130 million credit and debit cards.