SAN FRANCISCO INTERNATIONAL AIRPORT (CBS SF) — A United Airlines flight headed to Washington Dulles International Airport in Dulles, Virginia, from San Francisco International Airport rerouted back to SFO Wednesday morning because of an unspecified maintenance issue, a spokesman for the airport said.

United Flight 408 returned to SFO and landed around 8:30 a.m., according to airport spokesman Doug Yakel. The Boeing 777 had a scheduled departure of 7:30 a.m.

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The Boeing 777 had 269 passengers and a crew of 11.

Airline officials said around 10:30 a.m. that a different plane will be used to take those passengers to their destination.

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United issued the following statement: “United flight 408 from San Francisco to Dulles returned to San Francisco after reports of a mechanical issue. The flight landed safely and we are working to get our customers back on their journey this morning.”

As of 9:15 a.m. the plane was still at the gate, and Yakel had no estimate for when the flight would get back in the air.

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United Airlines officials were not immediately available for comment.