A St John spokeswoman said it received a call to an incident on State Highway 88 at Blanket Bay about 8.10am. Two ambulances responded to the scene and two patients were treated for minor injuries, one of whom was transported to Dunedin Hospital, she said.
A police spokeswoman said the incident was a three-vehicle crash which involved a truck and two cars.
A Fire and Emergency New Zealand spokeswoman said one crew from Port Chalmers Station attended the crash and assisted at the scene.
Another crew from Willowbank Station was dispatched but was not needed, the spokeswoman said.
An Otago Daily Times photographer at the scene said a truck carrying a container appeared to have rear-ended a car which then rear-ended another car.
The incident caused significant traffic disruptions for about half an hour and commuters and pupils could be seen stranded at bus stops.
The road was cleared by about 9.05am, he said.