DENVER -- Southwest Airlines experienced a computer issue that delayed thousands of passenger at Denver International Airport and nationwide for several hours Wednesday afternoon.
DIA reported the problem was resolved and operations at Southwest returned to normal by early Wednesday evening.
But several hours later frustrated passengers were still have trouble getting on flights. The airport sent a message about cancellations and delays Wednesday night.
The airline tweeted just before 1 p.m. MDT that it was aware and investigating the current issues. Southwest promised to update travelers on Twitter when it has updates.
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The airline's airport kiosks and website were not available for check-in or booking.
Some passengers reported that Southwest was issuing handwritten paper tickets to get fliers back in the air.
Southwest Airlines is the No. 4 U.S. airline by passenger traffic.
The airline issued a statement Wednesday afternoon
“Southwest Airlines began experiencing intermittent performance issues earlier this afternoon with multiple technology systems as a result of an outage. We are now managing flight delays across our system, with a temporary ground stop in place for those flights that have not left the gate. We apologize to our Customers whose travel plans are impacted. We have a Team of experts working diligently to resolve the technical issues and their efforts have systems gradually coming back online. We expect to continue our move toward a normal operation but believe it will take time."