SAN FRANCISCO — United Airlines flights were grounded across the country Wednesday evening due to a “technology issue.” 

Flights out of San Francisco International in California, George Bush Intercontinental/Houston in Texas, Denver International in Colorado, Chicago OHare International in Illinois, Ronald Reagan Washington National in Washington D.C,, and Newark International in New York are impacted, according to the FAA’s National Airspace System Status. Other airports may also be impacted. 

“Due to a technology issue, we are holding United mainline flights at their departure airports. We expect additional flight delays this evening as we work through this issue,” the company said in a statement. “Safety is our top priority, and we’ll work with our customers to get them to their destinations.”

The company is also replying to users on social media complaining about delays. 

“We’re sorry for any inconvenience caused. We are aware of the system error and our teams are working to resolve things to have you on your way,” the company wrote on X. 

“We apologize for the disruption today. Our teams are working to resolve the tech outage as quickly as possible, and we appreciate your patience,” they wrote to another user. 

When checking the status of flights on United’s website, delays range from an hour to over four and a half depending on the flight’s origin and destination. 

“We want you to know your flight is departing late because we are working to resolve a technology issue,” a message on the website reads for some flights with longer delay times. “We value your time and we’re sorry for the inconvenience.” 

No additional information is available at this time and it’s unclear what caused the error, or when it may be resolved.