The man was on the tracks near Convent Station when he was struck by eastbound Morris and Essex train 884 at 9:30 p.m., NJ Transit spokesman Paul Milo said.
The train had left Hackettstown at 8:32 p.m. and was scheduled to arrive in Hoboen at 10:34 p.m.
No injuries were reported to the eight passengers or crew on board at the time. New Jersey Transit Police are leading the investigation.
On Monday, a 17-year-old girl was killed by a Morris & Essex Line train in Long Hill.
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