Police say a Holden Commodore struck a Toyota Hilux ute on the Capricorn Highway, between Comet and Blackwater, just before 11am yesterday.

Four people inside the Commodore, including father Shaun Ranger, seven-year-old Baylee, six-year-old Chandler, and another man, were killed in the crash.

Ranger’s fiancé Renee and the couple’s youngest daughter Saphora, aged two, were travelling in a different car, behind the Commodore.

The family is understood to have been returning from a camping trip.

Inspector Ben Wiltshire said the mother was at the scene of the crash when police arrived.

“It was a very high-speed crash with significant damage to both vehicles, fire was involved and the injuries to the people involved were horrific,” Wiltshire said.

Two men in the ute, believed to have been driving to work, were also injured.

A 28-year-old man is in hospital in a serious but stable condition and a 27-year-old man was flown to a hospital in Brisbane with life-threatening injuries.

Wiltshire said it was too early to “lay blame” for the crash or speculate on whether charges will be laid.

A GoFundMe has been started for Renee and Saphora by friend Chantel Semple.

“Shaun, Baylee and Chandler were cherished and loved by many and brought so much joy and light into our lives,” Semple wrote.

She said Baylee had a “cheeky smile, bubbly personality and a love for horses”.

Chandler was described as a “sweet and kind hearted little boy, full of life (who) loved the outdoors”.

“We are all very heartbroken over this unexpected loss and want to give them the send off they deserve, a meaningful goodbye, surrounded by the people who love them,” the description reads.

Wiltshire said the incident was a “stark reminder of the fragility of life and importance of road safety”.

“These lives were cut short far too soon leaving families and loved ones to grapple with the unimaginable grief.

“The tragedy reverberates not just through the family but the entire Central Highlands community.”

He said police were working to determine the cause of the crash and urged drivers to be vigilant, avoid speeding, drive to conditions, avoid distraction and ensure they are well rested before long journeys.