A tractor trailer lost control on Highway 400 this morning just south of Barrie, causing a chain of events in which a cube van was pushed through the centre guardrail and into oncoming traffic.

The Ontario Provincial Police say that a southbound tractor trailer was slowing down for a collision in the distance, when it lost control at about 11:30 a.m.

The tractor-trailer rear-ended a cube van, which in turn went through the guardrail. Two other southbound vehicles also ended up being involved in the collision.

The cube van collided with a northbound Honda Civic and minivan.

The female driver of the minivan was taken to hospital with life-threatening injuries.

An Ornge spokesperson told CBC News that the female was in critical condition when initially transported to Barrie’s Royal Victoria Hospital. An Ornge air ambulance was then called to transport her to a Toronto hospital.

No other injuries were reported.

In addition to the collision investigation, there was also a need to clean up diesel that spilled as a result of the crash.

The southbound lanes were partly reopened by the supper hour, followed by northbound lanes which reopened shortly before 10 p.m. 

Last week, a pileup involving 96 vehicles shut down the same stretch of Highway 400 for hours.