Thanksgiving Day holiday shoppers line up with television sets on discount at the Target retail store in Chicago, Illinois, November 28, 2013. REUTERS/Jeff Haynes Target's CEO openly apologized today for the hack that swiped data from about 40 million credit cards.

He also said all Target customers will get a 10% discount on Saturday and Sunday. The deal is only good for one transaction and in store only.

Here's the apology:

Yesterday we shared that there was unauthorized access to payment card data at our U.S. stores. The issue has been identified and eliminated. We recognize this has been confusing and disruptive during an already busy holiday season. Our guests’ trust is our top priority at Target and we are committed to making this right.

We want our guests to understand that just because they shopped at Target during the impacted time frame, it doesn’t mean they are victims of fraud. In fact, in other similar situations, there are typically low levels of actual fraud. Most importantly, we want to reassure guests that they will not be held financially responsible for any credit and debit card fraud. And to provide guests with extra assurance, we will be offering free credit monitoring services. We will be in touch with those impacted by this issue soon on how and where to access the service.

We understand it’s been difficult for some guests to reach us via our website and call center. We apologize and want you to understand that we are experiencing unprecedented call volume. Our Target teams are working continuously to build capacity and meet our guests’ needs.

We take this crime seriously. It was a crime against Target, our team members, and most importantly, our guests. We’re in this together, and in that spirit, we are extending a 10% discount – the same amount our team members receive – to guests who shop in U.S. stores on Dec. 21 and 22. Again, we recognize this issue has been confusing and disruptive during an already busy holiday season. We want to emphasize that the issue has been addressed and let guests know they can shop with confidence at their local Target stores.