A jackknifed tractor trailer has closed all southbound lanes of Highway 400 near Cookstown.
OPP Sgt. Kerry Schmidt says a heavy-tow truck is on scene and there are no injuries.
At this time, it is unclear how long it will take for the crash to be cleared.
There will be significant delays in the area and detours will be in place.
It is unclear if weather was a factor in the crash.
Emergency crews are on scene, and there are no reports of injuries.
This is a developing story and more details will be provided as they become available.
