Target was breached by hackers during the holiday season this year, leaving the attackers with more than 70 million credit card numbers from shoppers who had visited Target’s retail stores between Nov. 27 and Dec. 15. The U.S. government is concerned enough with the attack that the Justice Department recently confirmed it’s investigating exactly what happened, and how.

The Target data breach that has affected up to 110 million people is now under scrutiny by the US Justice Department. Speaking before the Senate Committee on the Judiciary on Wednesday, US Attorney General Eric Holder said his office is evaluating and enforcing “privacy protections and other safeguards concerning data possessed by government as well as the private sector.” More specifically, Holder said that his office is trying to find the criminals who are behind the Target data breach and anyone who might be using the stolen information for gain.