A man fighting for life after a head-on crash on a Queensland highway that claimed the lives of four people has suffered a series of horrific injuries — including rupturing the largest artery in the human body.

Jonathan Green, 27, and his friend, 28, were in a Toyota Hilux that was hit head-on by a Holden Commodore on the Capricorn Hwy, between Comet and Blackwater in the state’s Central Highlands, just before 11am on Sunday.

WATCH THE VIDEO ABOVE: One of the worst weekends on Queensland roads.

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All four occupants of the Commodore — Corey Bietzel, 32, his friend Shaun Ranger, 28, and Ranger’s two children Baylee, 7, and Chandler, 6 — died at the scene.

Green was airlifted to Brisbane, while the 28-year-old was taken to a local hospital in a serious but stable condition.

It is believed the pair had been travelling for work.

Green is originally from Randfontein, Gauteng, in South Africa, but is understood to have lived in Australia for several years.

His sister Elizma Van Zyl said her brother has suffered significant injuries and is expected to have ongoing surgeries over the next four to five months as he recovers from the crash.

“He ruptured his aorta and lost all of his stomach muscles,” she said.

“He also has dead tissue and muscle that needed to be removed.”

Van Zyl said her brother was “fortunate” to have survived the accident and her heart “goes out to the families that lost their loved ones”.

She has started a Givealittle fundraiser to help cover the costs of her brother’s medical care, recovery costs, and basic necessities once he is stable.

The horror crash tore apart a family of five, with Ranger’s fiancee, Renee Carla, now a single mother to the couple’s youngest daughter, Saphora, 2.

The group in the Holden Commodore had been returning home from a camping trip, with Carla and Saphora travelling behind them in another car.

Chantel Semple, a friend of Carla’s, said Baylee had a cheeky smile and a love for horses, while Chandler “was a sweet and kind-hearted little boy” who enjoyed the outdoors.

“Shaun (was) a dedicated and selfless father, supportive friend and loving partner,” Semple said in a fundraiser she set up for the family.

“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.”

On Monday, Bietzel was identified as the fourth deceased victim of the crash as his family shared a touching tribute describing him as a “loving son, grandson, a devoted father, brother, cousin and friend”.

His cousin Taya-Marie Harper said he “touched the hearts of many people and left an irreplaceable void” and the family are “heartbroken over this unexpected loss”.

“Corey was loved and cherished by many and brought much joy and light to people’s lives,” she said.

Harper has launched a GoFundMe to help support her family as they prepare to give Bietzel “the send off he deserves”.

Following the crash, the Capricorn Hwy was closed in both directions for several hours while police remained at the scene.

The Holden was completely destroyed in the crash and the wreckage was left crumpled on the side of the highway while the ute had flipped onto its roof.

Inspector Ben Wiltshire said both of the vehicles had caught fire on impact.

He said it was a “high-speed” crash but that the exact circumstances were still being investigated.

Wiltshire said the injuries the victims sustained were “horrific”.

“There is a complex investigation that takes place for every fatal traffic accident and this was no exception,” he said.

“We need to conduct a thorough investigation before we make any decisions about charges.”

Wiltshire said the tragedy would reverberate throughout the entire Central Highlands community.

As a result of the accident, police will be ramping up traffic enforcement efforts throughout the region.

“This heartbreaking incident serves as a stark reminder of the fragility of life and the importance of road safety,” Wiltshire said.

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

Eleven people were killed on Queensland’s roads over the weekend, including three teens who crashed into another car while trying to overtake a semi-trailer in Mackay on Friday night.

Two of the teens have been identified as T-Jay Petrass and Liam Doumergue, both 19, while a 19-year-old girl also travelling in their car was killed.

Also on Friday a 21-year-old girl was killed in a head-on collision in the Gympie Region, while a 26-year-old man died falling out of a car in Tamborine.

Police are also investigating after a car hit and killed an 18-year-old man lying on the road in the South Burnett region on Saturday morning.

Later that morning a 45-year-old motorbike rider died when he crashed into a trailer being towed by a ute in Mackay.

Wiltshire urged motorists to drive to the conditions and said a split-second decision could be a matter of life or death.

“Don’t speed, drive to the conditions, avoid distractions and ensure that you’re well rested before embarking on any long journey,” he said.

“Our families, our friends and our children are depending on you.”