BLYTH, ONT. -- A section of Highway 4 between Blyth and Londesborough was closed following a head-on crash Thursday morning. 

Police say a tractor trailer and an SUV collided around 9:30 a.m.

The driver of the SUV was taken to hospital by air ambulance with serious but non-life threatening injuries.

The two drivers were the only occupants in both vehicles.

The SUV was left on it's side with its roof removed.

Highway 4 was closed for much of the day for the police investigation.