Three people are dead after a vehicle struck a concrete bridge and ended up on its roof in a ditch in Alliston, Ontario Provincial Police confirm.

It happened on Adjala Tecumseth Townline between 10th and 11th Line.

Police discovered the wreck at around 8 a.m. Sunday, but are not sure when the accident actually occurred.

"It is still very unclear what actually occurred, but it was a single vehicle that left a roadway into the ditch," Const. Dave Woodford told CP24 early Sunday afternoon. "It's very tragic."

Adjala Tecumseth Townline was closed off as police conducted an accident reconstruction at the scene. The road reopened shortly before 5:30 p.m.

The victims are not being identified pending next-of-kin.

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