UPDATE: The death toll has risen from a truck rollover west of the Darling Downs this morning with 163 sheep dead and more injured.
One lane of the Mitchell Hwy 20km south of Charleville remains closed as council workers clear the scene of a B-triple rollover from this morning.
Charleville police Senior Sergeant Adrian Rieck said 163 of the 1200 sheep loaded on the truck had died and an estimated 60 more injured and currently trapped in the middle trailer.
He said those sheep would be assessed by council workers onsite as soon as access was possible.
Heavy vehicle recovery machinery is en route from Dubbo to assist in clearing the scene and righting the three felled trailers.
While investigations are continuing, Snr Sgt Rieck said police would look into whether fatigue and driver inattention were contributing factors to the rollover.
He said initial information suggested the prime mover had been heading north along the highway headed for Longreach when it cross to the southbound lanes and the male truck driver attempted to correct the vehicle.
Snr Sgt Rieck said that may have led to the truck trailers rolling.
The truck had been headed to Longreach from Dubbo.
One lane of the highway is expected to remain blocked until early this evening.
EARLIER, 8.30AM: More than 150 sheep have been killed in a road train rollover west of the Darling Downs this morning.
A B-triple road train carting about 1200 sheep on the Mitchell Hwy, 20km south of Charleville, rolled shortly before 1.50am.
Charleville police Senior Sergeant Adrian Rieck said about 150 sheep had been killed on impact when the rear trailers of the B-triple configuration rolled off the highway.
He said more sheep had been injured but the extent of their injuries was as yet unknown as emergency services continue to clear the area.
Snr Sgt Rieck said investigations were under way into the cause of the rollover but initial information suggested no other vehicle had been involved.
He said the driver of the truck, who was uninjured, was not under the influence of any substances.
"The driver is uninjured which is the main thing as these matters can quickly become fatalities," he said.
"At this stage, the southbound lane of the highway will remain closed for another four to five hours as heavy vehicle recovery comes up from Dubbo to move the truck.
"Police and council are on site doing traffic control."
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