The southbound Highway 400 has reopened after a dump truck with its box up allegedly hit an overhead sign around 4 a.m. Thursday.

The closure lasted for about five hours until 10 a.m. while crews fixed the dangling sign and its support structure at Teston Road.

“It’s not just the sign board itself but the actual structure itself which is compromised,” OPP Sgt. Kerry Schmidt said early Thursday morning. “It’s sagging down and there is fear that it could collapse.”

CP24's cameras showed that traffic was already heavily backed up for kilometres in a stop-and-go, gridlocked situation by 6 a.m. Many vehicles got stuck between King Road in the north and Teston road. Police were turning them around so they could exit at King Road.

Schmidt said witnesses told police that the driver of the dump truck pulled over for a while, but then left the scene. They are looking for tips to help identify the driver.

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