UPDATE: OPP announced Highway 401 has since reopened in a tweet posted at 2:29 a.m. Thursday.
OPP tweeted a warning just after 3 p.m. Wednesday regarding a collision on the highway between Colonel Talbot Road and Union Road.
A tractor trailer was involved, and was blocking westbound lanes, they said.
Just after 3:50 p.m., OPP tweeted an update, warning Highway 401’s westbound lanes are closed at Colonel Talbot Road.
Extreme congestion continues on the 401 between Mill Road and Southminster Bourne.
Traffic on eastbound highway 401 is not affected.
More to come.