SAN FRANCISCO (AP) — Target suffered a technological glitch that stalled checkout lines at its stores worldwide Saturday, exasperating shoppers and eating into sales at a prime time for retailers.

The outage periodically prevented Target's cashiers from scanning merchandise or processing transactions. Self-checkout registers also weren't working at times, causing massive lines in some stores.

Target temporarily closed some of its stores rather than risk aggravating shoppers.

Target acknowledged the checkout headaches in a tweet and apologized for the inconvenience Saturday afternoon.

The cashiers were back up and running Saturday evening.

Following the shopping debacle, Target responded to media inquiries with the following statement:

"Target’s registers are fully back online and guests are able to purchase their merchandise again in all stores. The temporary outage earlier today was the result of an internal technology issue that lasted for approximately two hours. Our technology team worked quickly to identify and fix the issue, and we apologize for the inconvenience and frustration this caused for our guests. After an initial but thorough review, we can confirm that this was not a data breach or security-related issue, and no guest information was compromised at any time. We appreciate all of our store team members who worked quickly to assist guests and thank everyone involved for their patience."