A vehicle fire on the Decarie at 3:20 p.m. ET forced the closure of southbound lanes at the Jean Talon exit.
"Two vehicles collided and one [caught] on fire," Sgt. Gino Pare of the Quebec provincial police. "No one was hurt."
Just before 4:30 p.m. ET, two of the three lanes were reopened.
The closure affected traffic on Highway 40, triggering bumper-to-bumper congestion for nearly seven kilometres.
Another crash on Highway 20 West just after 3 p.m. ET backed up traffic beyond the Turcot Interchange. Three vehicles were involved in the crash, but no injuries were reported.
All three lanes of the 20 West remained closed at 4:45 p.m, but traffic is being diverted to the left shoulder to avoid the accident.
CBC traffic reporter Jeremy Zafran is advising drivers to avoid the main routes as they make their way home.
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