Two of the four friends killed when their car was T-boned on an isolated Victorian road held hands as they died from internal injuries.
The four women, aged 64 to 75, were on their way home from line dancing when their car was slammed into at an intersection at Navarre about 6pm on Saturday.
"Seeing that scene, it was horrific...four women who looked like they were just asleep, so they've died from internal injuries," Assistant Commissioner Doug Fryer told reporters on Sunday.
"The sight of the driver holding the passenger's hand as she passed will haunt me for some time."
The women were driving in a Kia Rio on an isolated, clear stretch of road in a 70km/h section when the other car came straight through an intersection in an 80km/h zone, Mr Fryer said.
"The elderly women had no chance whatsoever, there was no opportunity to take evasive action," he said, adding the intersection had no history of significant crashes.
Four people from a nearby house came out to help before emergency services arrived.
The 64-year-old woman driving the other car was taken to hospital where she had blood samples taken. She will be interviewed by police.
Two Hamilton women, aged 75 and 74, a 72-year-old Portland woman and a 64-year-old Heywood woman died in the crash.
"They've been in the community for decades, they've been valued members within the community for decades," Mr Fryer said.
The Cactus Moons Linedancing group posted on Facebook on Saturday.
"It is with a heavy heart we must tell you that four of our linedancing family senselessly and tragically lost their lives after dancing with us at St Arnaud on Saturday," it wrote.
"This is truly heartbreaking for everyone and we extend our sympathy to their loved ones and to their friends where they dance at Hamilton."
Victoria's road toll now stands 78, with eight people killed on Victoria's roads since Saturday morning.