UPDATE: Police are appealing for witnesses after a serious crash south of Toowoomba left a man in a critical condition.
The Forensic Crash Unit is investigating after the crash on Toowoomba Karara Rd, south of Leyburn about 9.20am yesterday.
Police said a green 2002 Holden Commodore, with registration 591 XJI, was travelling north on the road when it left the road and collided with a tree.
The driver of the car, a 35-year-old man, was transported by the Toowoomba-based RACQ LifeFlight helicopter to the Princess Alexandra Hospital where he was last night still in a critical condition.
A second man was also airlifted from the scene in a stable condition to Toowoomba Hospital.
Police want to speak to a witness who was first on scene who may be able to help with investigations.
The witness is described as being Caucasian with grey hair, slim build, aged in his 50s and wearing a red jumper.
Anyone else who witnessed the incident or has information, including dash cam footage is asked to contact Policlink on 131 444.
EARLIER: FIVE people have been injured in a crash on the Toowoomba-Karara Rd, with one man left with serious injuries.
A Queensland Fire and Emergency Services spokeswoman said one person was trapped in the car, which had crashed into a tree, and crews had to cut open the roof to free him.
A Queensland Ambulance Service spokesman said a man was being treated for serious injuries, while a 35-year-old woman had hand injuries, a 13-year-old boy had minor head injuries, a five-year-old boy had hand injuries and neck pain and a 10-year-old boy had an ankle injury.
The crash happened at about 9.30am, three kilometres south of Leyburn.
The LifeFlight helicopter at the Rescue 500 helicopter are both currently on scene and will be transporting the injured patients.
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