GO Transit’s Lakeshore West line reduced its service to hourly trains for the rest of Saturday as crews work to fix unstable track conditions between two stations.

On Saturday morning, crews determined that tracks between Port Credit and Clarkson GO stations became “unstable for trains to safely pass.”

"Given all the rain power that we've seen actually all week, we have our crews do extra track patrols, and crews noticed the instability near the tracks," Metrolinx spokesperson Anne Marie Aikins told CP24 Saturday afternoon.

"Once they started to investigate it, they realized just how unstable and extensive it was beneath the tracks. And that's just not safe to operate trains overtop of it. And we won't take any of those risks, so the trains were all stopped."

Aikins added that the cause of the instability is not yet known, but it is being investigated.

"We're bringing in extra resources to ensure people can get around tonight and safely with all of the things going on. And that's our first priority," she said.

Trains are running between Port Credit GO and Union Station, and between Clarkson GO and West Harbour GO.

Trains, however, were not running between Clarkson and Port Credit stations during the repairs. A GO shuttle bus service is in place between the two stations.

Repairs were complete in time for the start of regular service on Sunday morning.

GO Transit is expecting passenger volumes to increase this afternoon into the evening due to Halloween parties, the Leafs game, and other events in the city.

“There is a way to get there, and you just need to plan ahead. Check for the services. And know we're doing the best we can to get this repaired as soon as possible,” Aikins said.

Metrolinx staff are at GO stations to assist customers.