Passing motorists watched as a trailer unit, carrying wool bales, slid off State Highway 1 near Waikouaiti yesterday and dragged its truck down a steep bank.
Emergency services were called after the northbound truck-and-trailer unit left the road, landing in a paddock, 200m north of the Waikouaiti bridge, just after 1pm yesterday.
The 49-year-old driver was treated by St John staff before being taken to Dunedin Hospital by Otago Regional Rescue Helicopter. He was last night in a stable condition with moderate to serious injuries.
Constable Jon-Paul Tremain, of Waikouaiti, said witnesses saw the trailer begin to lean as the truck went around a bend.
''It almost happened in slow motion, before going over, dragging the cab with it.''
Red paint from the Linfox truck could be seen along the road barriers before the point where it left the road. Wool bales were strewn around the paddock.
Const Tremain said speed might have been a factor and the serious crash unit was investigating. The road was reduced to one lane for just over an hour.
