Neiman Marcus says 1.1 million debit and credit cards used at its stores may have been compromised in a security breach last year.

The high-end retailer said Visa, MasterCard and Discover have found 2,400 Neiman Marcus and Last Call customer cards that were used fraudulently. Last Call is Neiman Marcus’ clearance chain. Neiman Marcus says it is notifying all customers who shopped in its stores in 2013 and offering them a free year of credit monitoring and identity-theft protection.