Service on the No. 7 New York City Subway line between Queensboro Plaza and Times Square was suspended on Monday after authorities were alerted to smoke-like conditions, the FDNY said.
The FDNY was alerted at 8:41 a.m. ET, it said, adding that a rescue train had been sent in order to evacuate about 550 passengers. There have been no injuries reported thus far, the FDNY added.
The Metropolitan Transportation Authority, the city's agency responsible for its Subway system, told NBC New York the train stopped as though someone pulled the emergency brake, though it remains unclear whether or not it was pulled.
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Authorities also said the smoke-like conditions were created by a disabled contact shoe, which connects to the train's electrified rail, the report added.
By 10:32 a.m. ET, the MTA said the train would be running with delays in both directions.
Read the full story from NBC New York here.