Amtrak and New Jersey Transit trains share the same tracks at the station.

Amtrak officials said shortly after the derailment that passengers should expect lengthy delays. Long Island Railroad trains, which also operate at the station, were not affected.

Early Friday, some New Jersey Transit service into Penn Station was restored, with delays up to 90 minutes. It was unclear how the derailment would affect service during the Friday morning commute. New Jersey Transit tickets will also be honored on PATH trains and New Jersey Transit buses on Friday, the agency said.

At Penn Station, a crowd of people filled the concourse on Thursday night and expressed frustration over another disruptive episode there. The latest derailment set Twitter ablaze as riders assailed their transit system for its deficiencies, complained that their trains were delayed, and stewed about the impact the derailment would have on their morning commutes. Peter Everett, who said he was waiting for his girlfriend to arrive on an Amtrak train, said he was not surprised by the derailment.