SAN FRANCISCO (CBS SF) -- A Muni Metro train caused damage inside a subway tunnel Thursday , leading to major delays throughout the system during the afternoon commute.
Underground service was knocked out after an inbound N train dislodged a power source in the tunnel at Duboce and Church streets late Thursday morning, San Francisco Municipal Transportation Agency spokesman Paul Rose said.
A piece of equipment on top of the vehicle—the pantograph, which connects the vehicle to Muni's overhead wires—apparently broke minutes earlier when the train was near Second Avenue and Irving Street, Rose said.
When the train entered the tunnel, it dragged down the wires in a section of the tunnel before the underground merger with other Muni Metro lines, but it also disrupted the power source for the K-Ingleside, L-Taraval and M-Ocean View lines.
For about six hours, there was no underground service between Church and Embarcadero stations. Crews were able to restore power to the K, L, and M by 5:30 p.m., but Rose said that the N and J underground service was not expected to be restored until Friday morning.
Affected passengers can take another Muni Metro train to Church station and transfer aboveground to a J or N vehicle, among other alternatives, Rose said.
"We're planning to work overnight to make sure that it doesn't affect the morning commute," he said.
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