Representatives from the retailer confirmed the security breach Saturday, saying it's not clear if credit card data was at risk, and if so, how many customers would be affected.
The breach was first reported by cybersecurity reporter Brian Krebs, who said there was an increase in fraudulent credit and debit card charges on cards customers had used at Nieman Marcus.
Nieman Marcus was first notified of the potential breach by its credit card processor in December and the retailer subsequently notified authorities.
The company hasn't issued a statement regarding the security breach, but did post a brief message apologizing to customers on Twitter.
The security of our customers' information is always a priority and we sincerely regret any inconvenience.— Neiman Marcus (@neimanmarcus) January 11, 2014
The potential breach of credit card information doesn't appear to be nearly as extensive as that of fellow retailer Target, where some 100 million customers were affected.