Train service along the Northeast Corridor south of New York City ground to a halt Wednesday evening because of fallen overhead power cables in Kearny, N.J., stranding commuters and travelers on trains and at stations as far south as Washington.

The power outage disrupted service between New York and Newark, starting at 5:05 p.m. and the backups cascaded down the corridor that is the main line between New York and Washington. Some trains bound for Pennsylvania Station in Manhattan, America’s busiest rail hub, terminated in Philadelphia, where passengers were left to find alternate transportation, said Jason Abrams, a spokesman for Amtrak.

At 10:05 p.m., hundreds of people rushed the entryway of track 11 at Penn Station, where a train to Trenton was boarding nearly four-and-a-half hours behind schedule.

At about 10:30 p.m., Mr. Abrams said trains were running again south of Penn Station. By 11 p.m., he said, northbound service had also resumed. But delays and cancellations could continue on Thursday because of the “residual impacts” of Wednesday’s chaos, New Jersey Transit said on social media at about 11:30 p.m.

Sheydline Moise, 23, was shuffling forward in the crowd. She’d left work to catch a 6:27 p.m. train home toward Woodbridge, N.J., and had been waiting at the station ever since. At one point, she boarded a train for about 20 minutes, only for authorities to tell passengers to disembark, she said.

“I almost started to cry,” Ms. Moise said, adding that Uber was quoting a fare of nearly $200. “This has been a super long night,” she said, sounding exasperated. “I’m definitely calling off tomorrow.”