Six dead after horror night on Victoria's roads at end of National Road Safety week

All four women in the Kia died at the scene.  The 64-year-old driver of the other vehicle, from Stawell, was taken to hospital with non-life-threatening injuries. She is yet to be interviewed by police.

The victims were a 64-year-old Heywood woman, 72-year-old Portland woman, and 74- and 75-year-old women from Hamilton.

"All of them, we believe, had been in the town of St Arnaud, line dancing, and they were on their way home," Assistant Commissioner Fryer said.

"There was nothing they could have done to avoid being hit.

"We've got four women who have had a great day, on their way home to family, and at the blink of an eye four of them lost their lives.

"Someone has just come through, has not seen a stop sign, and has come through at speed."

About 2.30am on Sunday, a man who is yet to be identified, died after a crash in Heathcote Junction, north of Melbourne.

Police believe the driver was travelling north on South Mountain Rd when he lost control and drove through a farm fence.

Four passengers in the car were uninjured, but the driver died at the scene.

In Drysdale, near Geelong, a man in the front passenger seat of a car was flown to hospital with life-threatening injuries after a crash just before 2am.

Investigators believe the driver lost control and hit a power pole while driving on Carolanne Drive.

The second male passenger was uninjured and the 18-year-old driver suffered minor injuries and is assisting police with their enquiries.

Earlier in the night, about 10.30pm, a driver died in a single-vehicle collision in Bright, in north-east Victoria.

Police believe the driver was heading west on the Great Alpine Road when his car left the road and crashed into a tree.

Emergency services treated him, but he died before being taken to hospital. He is yet to be identified.

Major Collision Investigation Unit detectives are investigating the Navarre crash that killed the four women.

Assistant Commissioner Fryer said the deaths would rip apart three communities.

"We're now delivering four death messages because a woman made a simple mistake and we implore everyone just to pay so much more attention on the roads," he said.

"We've got four women who won't see Christmas; they're mothers, they're grandmothers, they're wives and they're certainly friends, and buried in the community.

"So, you'll have three communities now grieving the loss of these women."

The six deaths bring the state's road toll up to 78. It was 89 at the same time last year.

The annual Road Trauma Support Services Victoria walk around Albert Park Lake marks the end of National Road Safety Week today.

The campaign aims to advocate for safer roads and raise funds to support people impacted by road trauma.

Cameron Sinclair, Road Trauma Support Services Victoria chief executive, said the road toll reaches far beyond the number of deaths and injuries each year.

“We must also come together in support of the people in our midst who live with the reality of road trauma, be they bereaved family members and friends, the injured, drivers involved in road crashes, emergency service workers and witnesses," Mr Sinclair said.

If you have any information on any of the crashes overnight, police are urging witnesses to contact Crime Stoppers on 1800 333 000 or visit crimestoppers.com.au

Road Trauma Support Services Victoria offers support and counselling to anyone impacted by a road collision 1300 367 797.