OPP are re-opening Hwy. 401 after a multi-vehicle crash led to a roughly five hour closure through Chatham.

The crash happened in the construction zone near Communication Rd. just before 4pm.

Police are directing traffic off Hwy. 401 westbound at Kent Bridge Rd. and eastbound at Bloomfield Rd. Despite the lanes being re-opened, the backlog of traffic may be slow to clear and reach highway speeds.

OPP Constable Jay Denorer says three transport trucks and two vehicles were involved in a "chain reaction" crash after a truck stopped suddenly. Two trucks managed to come to a stop safely, but Denorer says a third truck wasn't so lucky.

"The third transport truck in the line collided into the back of the second which then caused the second transport truck to collide with the first one. Two motor vehicles behind all of them collided into each other and the third transport truck," says Denorer.

A chain reaction crash involving three transport trucks creates long delays on Hwy. 401 through Chatham on August 10, 2017. (Photo courtesy OPP)

One driver sustained minor injuries in the crash, but Denorer says a string of crashes causing injury and even death are becoming a serious concern.

"For some reason this year this has become a problem area. Last year construction was done in the same area and there wasn't as many collisions, this year it seems like a weekly occurrence," says Denorer. "The MTO and Coco Paving have put up more signs warning drivers to slow down, be cautious, give space."

He tells AM800 News people need to pay attention and expect to stop in a construction zone.

"Pay attention in front of you, don't be distracted, slow down, and give yourself room in the construction zone so that you can safely come to a stop if you have to," says Denorer. "During the peak rush hour times traffic gets heavy in that area and you're actually going to slow down and come to a stop on the 401."

Denorer says charges are pending in relation to the crash.