Service has resumed with delays on the downtown, 4, 5 and 6 subway lines after an earlier outage between the 125th Street and Brooklyn-Bridge-City Hall stations.
The MTA said the outage was because of switch problems at Union Square.
Straphangers are advised to expect delays on the entire line.
Some downtown 5 trains are running on the 2 line from 149th Street-Grand Concourse to Nevins Street.