It happened around 9 a.m. Wednesday near Weber and Clinton avenues.
When officers arrived, they found a woman they believe in her late 30s dead.
Investigators believe the woman may have accessed the train tracks through a nearby construction fence.
Officers do not believe foul play is involved and the investigation is ongoing.
The train is expected to be stopped for a few hours and is currently not blocking any roads.
Stay with ABC30 for the latest details on this developing story.