SAN FRANCISCO -- BART experienced temporary delays because of an equipment problem in the Transbay Tube, officials said.

A maintenance vehicle suffered a mechanical problem in the Transbay Tube shortly before 7:30 a.m. and caused delays of up to 20 minutes, according to BART officials.

Trains resumed normal service at 7:40 a.m. after the car was towed, officials added. No more delays were expected.

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