Update (6 a.m.): The westbound 401 between Marysville Road and Shannonville Road has now officially been opened after an 11-hour closure.
A tractor trailer fire caused the westbound 401 between Marysville Road and Shannonville Road to be closed early Saturday evening.
Tyendinaga Fire, along with tanker support from Mohawk Fire was called in to put out the flames on the westbound 401 at Marysville Road. They were eventually able to get the fire under control. Heavy smoke was also visible when firefighters arrived.
According to social media reports, traffic was backed up for several hours.
The Ministry of Environment and police also attended the scene.