SAN FRANCISCO -- A plane had to make an emergency landing at San Francisco International Airport on Saturday due to mechanical issues, though no one was injured, an airport spokeswoman said.

Around 3:50 p.m., an initial report came into the airport's control tower from United Airlines flight 378, which was arriving from Vancouver, said airport spokeswoman Shannon Wilson.

The pilot told the control tower he had declared an air emergency due to a hydraulic issue, but Wilson said she had no other details on what the issue entailed.

The flight, which had 107 passengers on board, landed safely and was towed to a gate. No injuries were reported.

Wilson said the filght was scheduled to land at SFO.

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