A 78-year-old Port Fairy man died in the head-on collision with a B-double milk tanker at Killarney on Thursday afternoon.

It's understood the man had recently suffered a bereavement in his family.

Warrnambool police highway patrol unit members are investigating the cause of the collision.

There will be a review of the circumstances of the accident to determine if the fatality will be included in the road toll.

A similar review will be conducted into the circumstances of a fatal collision just east of Darlington on Thursday last week.

A 49-year-old Terang man, the driver of a station wagon that was on the wrong side of the Hamilton Highway, died in the crash.

Thursday at 3.40pm: A man has died at the scene of a head-on collision between a tanker and a car on the Princes Highway, near Killarney before 2pm on Thursday.

Victoria Police Media confirmed the driver of the car was the sole occupant and he passed away after a head-on crash with a B-double truck.

The male is yet to be identified.

The driver of the B-double truck stopped and tried to assist the male.

Emergency services remain on the scene.

The Princes Highway is still closed and Victoria Police media said it would be for some time as the major collision unit investigation team are on their way to assess the scene.

Victoria's road toll is now at 134 this year, compared to 170 in 2019.

Earlier: Emergency services are on the scene of a serious crash between a B-double truck and a car on the Princes Highway.

The crash happened just before 2pm near Killarney.

A CFA media spokesperson said the crash occurred 100 metres west of Rocks Road on the Princes Highway.

"A B-double milk tanker collided with a car and the B-double is fully loaded with milk," the spokesperson said.

She said the milk was secure but the truck was leaking some fuel.

Country Fire Authority crews from Kirkstall and Koroit are on the scene along with Ambulance Victoria, police and State Emergency Services.

The highway is closed and diversions are in place.

Motorists are urged to take a detour around Lake View Road.

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