The driver of a minivan that rolled in "treacherous conditions" this morning has been flown to Dunedin Hospital with a serious arm injury.
Senior Sergeant Matt Scoles said the minivan's three passengers were treated for minor injures at the scene near Clarks Junction on State Highway 87 about 8.55am today.
They had been heading towards Middlemarch for a rail trial cycling tour.
Although police were yet to determine the cause of the crash, Scoles said the icy conditions made the road treacherous for motorists and "possibly played a part" on the moderate bend where the bus rolled, coming to a stop on its side.
The road had been closed temporarily, but one lane was now open, he said.
Scoles said it was too soon confirm if the driver would be charged.
"We will investigate and determine whether we need to take further action or not," he said.
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