(John Gress/Reuters file photo)

Hours after we learned that the hack against Target was much worse than initially feared, the retailer Neiman Marcus has also admitted it was compromised during the holiday season.

The attack was discovered in mid-December by Neiman Marcus's credit card processor, a finding that was confirmed by a third-party security company on New Year's Day. An unknown number of credit card numbers may have been leaked as a result, according to a corporate statement provided to the researcher and journalist Brian Krebs.

"We have begun to contain the intrusion and have taken significant steps to further enhance information security," the statement reads in part.

A Neiman Marcus spokesperson did not immediately respond to a question asking whether the company had completely sealed off the breach or conclusively identified the vulnerability that made the hack possible.

Given the coincidental timing, it's hard not to wonder whether the attacks on Neiman Marcus and Target are somehow related. On Friday, Target revised its impact estimate upward from 40 million affected customers to 70 million customers. But Neiman Marcus told Krebs it has no evidence to suggest a connection between the two hacks.