(NEW YORK) -- A morning commute for New Yorkers turned into a chaotic scene Tuesday when a subway scraped the side of a tunnel wall, forcing passengers to evacuate and walk underground through the smoke and darkness.
The southbound A train was just outside the 125th Street station in Harlem when the emergency break automatically turned on, according to Joe Lhota, chairman of the Metropolitan Transportation Authority. The train bucked forward and backward, causing two of the train's eight cars to derail and scrape the side of the wall, Lhota said. The train was 200 feet from the 125th Street and St. Nicholas Avenue station at the time.
That train was evacuated, Lhota said, as were three other trains in the same tunnel.
A total of 34 people were injured. Officials said most of the injuries involved smoke inhalation and none were life-threatening. Lhota said the smoke was caused by sparks and the garbage and sanitation along the tracks.
The incident, described by the New York City Emergency Management Department as a partial derailment, caused a power outage affecting all six tracks from West 119th Street to West 125th Street.
The FDNY said 500 passengers walked on the tracks, which Fire Commissioner Dan Nigro called “a dangerous thing” to do.
Lhota said investigators will determine why the emergency brake turned on.
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