Update August 22 10pm:
The Western Highway has reopened in both directions after a car rollover at Buangor on Thursday night.
The road closed near the intersection with colonial road after a woman in her 40s was trapped following the incident.
Victoria Police spokesman Senior Constable Alistair Parsons said the female driver in her 40s was taken via road to a Ballarat hospital in a stable condition
Hesaid the accident site was cleared and emergency services left the scene at 9.30pm.
It was suggested eastbound motorists divert onto the Pyrenees Highway at Ararat and westbound to divert onto the Beaufort - Lexton road at Beaufort.
Update August 22 6.30pm: The air ambulance helicopter has been dispatched to an area of the Western Highway east of Ararat, where a car has rolled over.
An Ambulance Victoria spokeswoman said a woman trapped in the vehicle was being assessed at scene, but the nature of her injuries had not yet been established.
Previously: Police from Stawell and Ararat, Country Fire Authority crews and Ambulance Victoria are on scene on the Western Highway at Buangor, after a car reportedly rolled over.
Ararat constable Josh Crawford said a woman was trapped and being treated by paramedics.
"Police are assisting with traffic control," he said.
A Victoria Police media spokeswoman, Senior Constable Melissa Seach, said the incident occurred west of Pope Road.
More to come.
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