The incident happened around 12:45 p.m. along the tracks in Sharon Hill, near Sharon Avenue.
Police say the man was walking south along fence line that runs along the train tracks when the high-speed Acela train came through.
Police believe the man had nowhere to go and was struck and killed. They believe the death was an accident, and that the man was not intending to hurt himself.
Train traffic was shut down in both directions as authorities investigated.
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