New Jersey Transit officials said commuters should expect significant delays on trains along Amtrak’s Northeast Corridor. Those trains were temporarily brought to a halt during much of the Wednesday evening commute because of a problem with the power supply. Service was restored at 5:45 p.m.

NJ Transit, whose trains run along Amtrak’s tracks heading south out of Pennsylvania Station in Manhattan, pulled many of its trains into the nearest station at about 4:35 p.m. and held them there, said Dan Stessel, a spokesman for the agency. The railroad then directed commuters to switch to buses or PATH trains, which were honoring their train passes, Mr. Stessel said.

The problem, a drop in voltage along the tracks, had affected all trains that run along the Northeast Corridor