By Betty Yu

SAN FRANCISCO (KPIX 5) — A man was rescued Thursday evening from the top of a San Francisco Municipal Railway train, fire officials said.

Service Castro station was delayed in both directions for about an hour, just before 8 p.m.

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Officials don’t know how the man got on top of the train or why. Firefighters helped him down a ladder. Officials tell us he was shocked by the overhead wires.

First responders wheeled the man into the back of an ambulance. Video showed him apparently using sign language to spell “help.”

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He was rushed to San Francisco General. His injuries were not considered life threatening.