Power Failure Brings Amtrak and N.J. Transit Trains to a Halt

New Jersey Transit and Amtrak train service in and out of New York City was again disrupted Friday morning, just hours after a power failure shut down all lines for more than three hours on Thursday and caused significant holdups around the nation’s busiest transit hub.

Amtrak said that on Thursday, one of the hottest days of the year, the loss of electricity had forced it to suspend all service for several hours along a 150-mile stretch of the Northeast Corridor. By Friday morning, train service was again snarled around New York City, where a disabled train in Manhattan’s Penn Station halted New Jersey Transit service in and out of the city and led to major delays for Amtrak.

A little before 8:30 a.m., Amtrak said that service between Philadelphia and New York would resume at noon. Kyle Anderson, a spokesman for the rail service, said in a statement that it was working to remove the disabled train and repair damaged infrastructure. Mr. Anderson also said that Amtrak was working with New Jersey Transit to identify the cause of Friday’s disruption.

Thursday’s outage rippled along the Eastern Seaboard, causing trains to be halted and canceled as far away as Boston and Harrisburg, Pa.

Gery Williams, an executive vice president of Amtrak, said the problem had emanated from “a malfunctioning circuit-breaker” in New Jersey, just west of the rail tunnels under the Hudson River, which cut electricity to the overhead wires that power trains into and out of the tunnels. That segment of the corridor has just two tracks and is the primary bottleneck for train travel in the Northeast. Any disruptions to that narrow passage can mean headaches for thousands of travelers.

Mr. Williams said the electrical problem was not related to a brush fire in Secaucus, N.J., on Thursday afternoon that was burning near train tracks and the New Jersey Turnpike. That fire was extinguished by Thursday evening.