(NewsNation) — United Airlines flights bound for major hubs across the country were grounded on Wednesday as the airline investigated a system error.

The outage affected airports including Chicago, Newark International Airport, San Francisco, Denver and Houston, according to FAA data.

"We are working with customers to get them to their destinations after a technology disruption on Wednesday evening," the airline told NewsNation in an update on Wednesday night.

"The underlying technology issue has been resolved, and, while we expect residual delays, our team is working to restore our normal operations."

Customers flooded X, formerly Twitter, seeking information about why they were stuck on the tarmac.

"United flights sitting on the Denver Airport tarmac due to computer issues in Chicag

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