The boy, described only as a minor, was struck by an eastbound Raritan Valley Line train west of the Bridgewater station shortly before 4:30 p.m. Monday, responders said.
Six people were aboard the train, which left Raritan at 4:16 p.m. and was due to arrive at Newark’s Penn Station at 5:15 p.m.
Services was suspended for more than 2½ hours between Raritan and Bound Brook.
NJ Transit police were investigating.
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