A person was transported to hospital in a serious condition after a car ploughed through a fence into a paddock, while another "spun around 180 degrees" on to the road.
Senior Sergeant Anthony Bond, of Dunedin, said police responded to a car crash at the intersection of McLaren Gully Rd and Allanton-Waihola Rd, State Highway 1, at 5pm on Friday.
A 19-year-old man had been travelling north, when he pulled over to the left side of the road to let a line of cars pass him.
He turned back into the road and crossed the centre line but failed to notice a vehicle travelling south behind a truck, driven by a 53-year-old woman, causing a crash.
The 19-year-old driver "spun around 180 degrees" to face back towards the highway, while the 53-year-old went through a fence and 50m up into a paddock.
A St John Hato Hone spokesman said one ambulance and a rapid-response vehicle were sent to the crash at 5.01pm.
One person was assessed by crews at the scene and was transported to Dunedin Hospital in a serious condition.
Earlier that day, at noon, police responded to another crash in Bradshaw St, South Dunedin.
A 21-year-old man had crashed into two parked cars.
"He thought he had enough room to squeeze through these while another vehicle was passing by, but has clipped the side of both of them," Snr Sgt Bond said.
The vehicle was towed away and no injuries were reported.