A woman who rolled her vehicle and crashed into a fence in a Taieri Plain paddock lost control after passing an ambulance, police say.
Senior Sergeant Anthony Bond, of Dunedin, said the 18-year-old was heading south from Dunedin on State Highway 1 near Henley at 10.40pm on Thursday.
She passed an ambulance in the passing lanes and lost control after passing.
She was not injured.