Four Winds Casino is warning customers that their credit card information may have been stolen during an attack on the casino’s payment card network.

A bank notified Four Winds on Oct. 2 that it had detected a pattern of unauthorized charges on bank cards after they were used at Four Winds, according to a news release from the casino.

Four Winds immediately launched an investigation and found that there was a criminal program installed that searched for and copied payment card information — such has cardholder names, card number, expiration date and internal verification code — as it was routed through the payment network.

Anyone who used a credit card at the Four Winds casino properties in New Buffalo, Hartford or Dowagiac or the Bent Tree service station in Dowagiac from October 2014 to Oct. 21, 2015, may be affected by the data breach.

The casino has new security measures in place to prevent future attacks and is working with payment card companies to identify potentially affected customers. Four Winds does not have a list of affected customers.

Four Winds is encouraging customers who may be affected by the data breach to closely monitor payment card statements and report any unauthorized activity immediately.