A Las Vegas company that owns casinos in four states says its system for processing credit and debit card information has been hacked.

Affinity Gaming issued a statement last week saying it has no evidence that is being stolen. Company officials say they've taken steps to secure the system, and the independent cybersecurity firm Mandiant was looking into the breach.

The announcement comes a few months after Affinity reported a different cyberattack. The said in December that its card processing system was infected with malware that compromised card data from customers.

Affinity owns 11 , including five in Nevada, three in Colorado, two in Missouri and one in Iowa.

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