The announcement came one day after a security blogger reported the issue.
The accounts would have been impacted between November 27th and December 15th.
In a statement, the company says they have worked closely with law enforcement and that the problem is resolved.
Target says they alerted authorities immediately after they were made aware of the problem.
Read more: http://nbcnews.to/1eqQVds
What to do if you think your information has been compromised: http://www.nbcnews.com/business/use-your-credit-card-target-heres-what-do-if-your-2D11775079
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