Warrnambool police Sergeant Tom Morris said a 26-year-old Port Fairy woman was driving a Suzuki swift west on the Princes Highway at Dennington when she conducted a U-turn at 2pm on Saturday.

He said a 1974 Kingswood was travelling behind the Suzuki.

"As the Suzuki has slowed down a collision has occurred," the sergeant said.

A 49-year-old male from Koroit was transported to Warrnambool Base Hospital with chest soreness.

Two primary school-aged girls in the Kingswood suffered cuts and abrasions and were also taken to hospital.

An Ambulance Victoria spokesman said the driver of the Suzuki suffered an arm injury and was transported to the same hospital in a different ambulance.

The incident occurred about 100 metres from the Dennington Bowls Club.

Sergeant Morris said members of the Warrnambool highway patrol unit attended the scene and waited for VicRoads to attend to clear debris off the road.

He said traffic was banked up on both sides of the freeway for about an hour.

Both vehicles were towed from the scene.

Sergeant Morris said the Kingswood was written off.

"It's my understanding it had only just been restored," he said.

"We are not investigating whether drugs or alcohol was involved. This was a matter of failing to give way."

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