All Northeast Corridor service on New Jersey Transit had been suspended in both directions between MetroPark and Trenton.
All four Northeast Corridor tracks are now open for use in both directions.
Amtrak has also resumed service between Philadelphia and New York City.
North Jersey Coast Line trains are still running with 20 minute delays in both directions.
A person on the tracks was fatally struck by an Amtrak train at about 3:55 p.m. Monday.
Commuters are advised to expect delays of up to an hour.