Passengers were told to expect delays Friday morning due to congestion at New York's Penn Station following an earlier train derailment.

New Jersey Transit said one of its trains was involved in a "minor," slow-speed derailment at the nation's busiest train station around 9 p.m. Thursday. A spokesperson for NJ Transit told News 12 New Jersey that the train was a North Jersey Coastline train headed from Long Branch.

About 180 passengers and crew members were on board. No injuries were reported.

Amtrak said Friday morning that crews worked overnight to assess the damage to the infrastructure, thoroughly inspected the tracks and completed any necessary repairs.

Amtrak said regular service has been restored in and out of Penn Station, but commuters should expect some “minor congestion-related delays.”

NJ Transit said it's working with Amtrak, which owns and operates the station, to determine the cause of the derailment.

It comes days before a massive repair project is slated to begin at Penn Station, which has been plagued by derailments, power failures and signal problems.

Gov. Chris Christie released a statement Friday morning, calling for a full investigation into the latest derailment's cause.