The unidentified woman was struck shortly after 7:30 a.m. just west of Main Street and Dewey Avenue, NJ Transit Chief Communications Officer Nancy Snyder said.
Agency officials initially believed the incident occurred in Little Falls because that's where the train stopped. Another look determined that it occurred on the Wayne side of the border.
No injuries were reported among the 52 customers and crew members on the Hoboken-bound train, which Snyder said left Lake Hopatcong at 6:40 a.m.
Service on the Montclair-Boonton line remained suspended Denville and Montclair State University into mid-morning. Substitute bus service was provided.
NJ Transit police were investigating.
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