B, D, F and M trains were hit with delays during the morning commute due to ongoing signal problems at the Herald Square station, according to the MTA.
There was no B train service between Brighton Beach Avenue and Bedford Park Boulevard in both directions, and no M trains between Broadway-Lafayette Street and Forest Hills-71st Avenue stations in both directions.
Forest Hill bound M trains were terminating at the Essex Streeet station.
Service later resumed with extensive delays.
The MTA advises that commuters allow for additional travel time.