An investigation continues into a single-vehicle crash that claimed the lives of four people in Victoria's west on Saturday.
The region's mayor confirmed four of the teenagers involved in the accident were students at Baimbridge College in Hamilton, about 300 kilometres west of Melbourne.
Police were yet to formally identify the victims on Sunday afternoon, but said two teenage boys, a teenage girl and a woman in her 30s died in the crash.
A 17-year-old girl, the sole survivor of the crash, was flown to the Alfred Hospital in Melbourne and remains in a critical condition.
Police believe the driver of the sedan lost control of the vehicle on Wannon-Nigretta Road near the small community of Bochara and hit a tree on Saturday morning.
Victoria Police Assistant Commissioner for Road Policing Glenn Weir said it was "a really traumatic and destructive scene".
"It is a really narrow, rural road that the vehicle has obviously been travelling at extremely high speed," he said.
Police were called to the scene by a passer-by after 9am on Saturday, but believe the crash could have occurred any time after about 1am.
Southern Grampians Mayor David Robertson said the accident hit his community hard.
"I think the town's still in shock, the families would certainly be grieving and the shock would be enormous for the immediate family," he said.
"The ripples that have gone out through the community have just been horrendous and a lot of the community are in shock, right through."
Mr Robertson said a trauma unit and grief counsellors would be on hand in the community from Monday.
"I think everyone in the community knows someone in the families, whether it's a grandma or a grandfather, uncles, aunties so forth. It's affected everybody," he said.
"It's an absolute tragedy for our small community here."
Community members band together in Hamilton
Major Collision Investigation Unit detectives examined the scene of the crash on Saturday and the vehicle was towed from the site on Sunday morning.
The interior and exterior of the car was decorated with handwriting in pen, including the words "drive safe" on the front passenger seat.
The crash occurred on a relatively quiet, rural road which runs near Hamilton Airport and the tourist attraction Nigretta Falls.
Hamilton resident Minnie Jackson told the ABC she went to school with some of the girls, who she believed were a year or two below.
"It was pretty upsetting," she said.
She said community was full of "really lovely people" who would band together in the wake of the tragedy.
Colleague Marissa Rodgers said it had been upsetting for everyone.
"It's going to be pretty hard on the whole community," she said.
'Catastrophe' on Victorian roads
Victorian Premier Daniel Andrews said the accident, coupled with the death of a young footballer in Kyneton, left two regional communities in grief.
"It's an incredibly difficult time for those families, friends, people who love those that have been caught up in this and we send our best wishes on what will be an incredibly challenging time," he said.
"People should be assured there will be full investigation on both counts, both fronts, so we can try and understand what has happened here."
The tragedy near Hamilton was one of a number of car crashes in the state in recent days.
A 73-year-old woman died in hospital and a truck driver from Jan Juc has been charged with dangerous driving causing death after a collision in Carag Carag on Friday afternoon.
Two people died after a single-vehicle crash in Thomastown in Melbourne's north about 7:20am on Sunday.
The driver, a 42-year-old man driver from Roxburgh Park, died in hospital. His passenger, a 42-year-old Thomastown woman, died at the scene.
"Since Friday, we've had a catastrophe on our roads," Assistant Commissioner Weir said.
A number of other people have been hospitalised after being involved in collisions across the state.
"None of these are accidents. They're collisions. They all have a cause and they could have been avoided," Assistant Commissioner Weir said.
There has been a nearly 30 per cent increase in the number of lives lost on Victorian roads in 2023 compared to the same time last year.
"We have seen a significant number of multiple fatality collisions," he said.
"It's unacceptable. It can't go on."
He said while Victoria Police had stepped up its efforts in tackling dangerous driving, he was making an appeal to all Victorians.
"They're the ones who can limit the carnage," he said.
"And it's to those people that I make the appeal right now to do something before you too either suffer road trauma or … you will know someone who does."
