UPDATE: A man crushed by a piece of heavy machinery has been airlifted to a Brisbane hospital after suffering serious injuries in the incident near Chinchilla.
A police investigation is under way to determine how a bucket detached from the loader on the Warrego Hwy about 10km west of the Western Downs town about 12.05pm.
"There was a loader driving westbound and for some reason it's lost control and tipped over, trapping a Chinchilla man in his 50s," Chinchilla police Senior Constable Justin Drier said.
The Warrego Hwy remains closed as traffic was cleared to allow the RACQ LifeFlight's Toowoomba-based Surat Gas Aero-Medical Service helicopter to land.
The man's family was by his side as the advanced care paramedics stabilised him at the scene.
Chinchilla Fire Station Captain Brian Colley said the quick actions of a passer-by helped free the man from under the machine's cabin before emergency services arrived on scene.
"The bucket has come unfixed from the loader, causing it to tip," Capt. Colley said.
"The man was pinned momentarily until a member of the public got a jack to lift the weight off him."
The man was airlifted to the Princess Alexandra Hospital in Brisbane in a stable condition.
The Forensic Crash Unit will investigate the incident.
1.50PM: Police are investigating after a man became trapped under a piece of machinery, suffering serious injuries.
Senior Constable Justin Drier said there had been no witnesses to the incident, which happened about 10km west of Chinchilla on the Warrego Hwy just after noon.
"There was a loader driving westbound and for some reason it's lost control and tipped over, trapping a Chinchilla man in his 50s," Snr Const Drier said.
The highway is closed to make way for a rescue helicopter.
The Forensic Crash Unit is investigating.
12.50PM: The Warrego Hwy is closed and traffic being cleared to make way for a rescue helicopter after an incident involving a tractor.
A man is believed to have suffered serious injuries to his lower body in the incident reported to authorities about 12.05pm.
Paramedics at the scene have stabilised the man who is expected to be airlifted to hospital.
Motorists are urged to avoid the area about 10km west of Chinchilla on the Warrego Hwy.
12.30PM: A man has suffered injuries to his lower body after an incident involving a tractor west of Chinchilla.
Initial reports suggest a man suffered leg injuries in the incident near the Warrego Hwy about 8km west of Chinchilla.
A Queensland Fire and Emergency Services spokesman said two crews had been tasked to a rescue mission on the Warrego Hwy near Chinchilla about 12.05pm.
He said the incident had occurred on the Warrego Hwy near the Western Downs town.
A Queensland Ambulance spokesperson said paramedics were on scene assessing the man who was in a stable condition.
"It looks to be an incident involving a tractor," the spokesperson said.
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