Service on the Lakeshore East GO Train between Oshawa and Toronto will be slower than usual for at least part of the morning due to a police investigation on the tracks west if Guildwood station.

Trains were holding, but authorities gave Metrolinx "permission to move trains slowly through area.

"Service will operate with delays until the investigation is done," the transit operator said on Twitter. 

Police investigations typically take up to three hours.