The fatal incident occurred at 3:45 p.m., and police completed their investigation after 7 p.m., according to Aaron Donovan, a spokesman for the Metropolitan Transportation Authority.
Donovan said authorities do not know why the man was on the tracks. The Croton-Harmon station in Croton-on-Hudson is on the Hudson Line of Metro-North about 30 miles north of Manhattan.
LoHud.com identified the man as Thomas Intrieri.
"Some passengers saw the young man who jumped in front of our #metronorth train at Croton-Harmon ... Very sad tragedy," said Tess Rose Lampert via Twitter @TessRose211.
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