The Suffern-bound train had left Hoboken shortly before 8 p.m. Thursday and struck him about an hour later west of the Paterson station, NJ TRANSIT said.
The body had to be retrieved from an elevated portion of the tracks, responders said.
None of the roughly 60 passengers and crew members aboard the No. 65 Main Bergen Line train were reported injured.
NJ TRANSIT police hadn't yet officially determined the circumstances and were investigating.
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