WASHINGTON (Reuters) -U.S. regional air carrier SkyWest Airlines cancelled about 700 flights because of an internal computer issue that crippled operations for five hours before it was resolved, the airline said on Thursday.

SkyWest provides regional service for key operators such as American Airlines, United Airlines, Alaska Airlines and Delta Air Lines.

A spokeswoman for SkyWest said the schedule changes included flight "cancellations into tomorrow morning, as we work to get crews and aircraft into position."

SkyWest added it was working "to return to normal operations as quickly as possible."

SkyWest confirmed the problem was a "server issue" that affected operations for about five hours.

Earlier, United Airlines said on its website that SkyWest was "experiencing a server outage that has impacted multiple airlines."

Aviation website FlightAware showed SkyWest flights beginning to resume late on Thursday.

(Reporting by David Shepardson; Editing by Christian Schmollinger and Clarence Fernandez)