(NEXSTAR) — Passengers scheduled to fly with Southwest Airlines reported delayed flights at airports in many parts of the country after the carrier experienced a system-wide outage early on Saturday morning.

Southwest Airlines said the issues are now resolved, but acknowledged that passengers may continue to face delays throughout the day.

“Some of our earliest departing flights were delayed this morning, and a handful of them canceled, after we experienced intermittent technology issues following routine overnight maintenance,” Southwest wrote in a statement shared with Nexstar. 

“We offer heartfelt apologies to our Customers for any inconvenience, and gratitude to our Employees who are working diligently to make it up to them.”

The delays are more likely to affect customers in Eastern and Central time zones, but secondary delays are possible for flights leaving further west, as well.

“We’ll continue to update Customers whose journey with us today might be delayed as result of the now-resolved issues,” the carrier said.