A computer system that airlines use for check-in kiosks, booking and more was experiencing issues on Tuesday, apparently affecting multiple air carriers.
There were widespread reports on social media of air passengers inconvenienced by the outage, with long lines at airports across the country.
Sabre Airline Solutions released this statement shortly before noon Eastern Time: "We are aware of the issues facing some of our customers. Recovery is in progress. We apologize for the inconvenience."
The company was tweeting that statement to people who took note of the outage.
American Airlines flagged the issue, saying in a statement that Sabre was "experiencing a technical issue that is impacting multiple carriers, including American Airlines. Sabre is working to resolve the issue as quickly as possible, and we apologize to our customers for the inconvenience."
American later said that the issue with Sabre's system "has been resolved."
NBC has reached out to Sabre about the outage and what might have caused it.
On its website, Sabre says its "technology is as essential to travel as air and water are essential to life."
New York Jets wide reciever Robby Anderson tweeted video showing a very long line of confused-looking people at Fort Lauderdale-Hollywood International Airport.
"The systems down n nobody can’t check in get boarding passes," Anderson wrote.