Train service on GO Transit's Barrie line will be delayed for up to several hours after a fatality near the Barrie South GO station.
South Simcoe Police confirmed a pedestrian has died after being struck by a train south of Innisfil Beach Road.
Trains will not be able to move through the area while emergency services investigate.
"Undoubtedly this is going to cause a major disruption for our Barrie customers, it's very unfortunate," said Metrolinx spokesperson, Anne Marie Aikins.
Metrolinx is advising riders they can use the Richmond Hill corridor stations as an alternate route.