Investigators are trying to get a clearer picture of the last moments before a fiery head-on crash that claimed the lives of a Queensland mother and her four young children.
The family died on Monday night after their station wagon slammed into an oncoming truck on Bunya Highway, south of Kingaroy.
Police want any witnesses to the accident, that claimed the lives of Charmaine Harris McLeod, 35, and her children Aaleyn, 6, Matilda, 5, Wyatt, 4, and Zaidok, 2, to come forward.
The tragic crash has left emergency crews, who fought through flames to reach the family, devastated they could not save them.
"This is a catastrophic incident scene, it's certainly one of the worst accidents I've ever seen," a police spokesman said.
Ms McLeod and three of the children died at the scene. A girl pulled from the car made it to hospital but died while on a rescue flight bound for Brisbane.
The truck driver was also injured but managed to free himself as the blaze spread to the surrounding grass.
Police say Ms McLeod was trying to overtake when her car slammed into the truck, which was travelling in the opposite direction.
They've also called for any dashcam footage to help them piece together exactly what happened.
Forensic testing was also underway on Wednesday to formally identify the family.
