A person sustained minor injuries when a vehicle rolled on State Highway 83 between Omarama and Otematata in the Waitaki District this afternoon.
A police spokeswoman said they were notified of the single-vehicle crash at 12.41pm.
A Fire and Emergency New Zealand (Fenz) spokeswoman said crews from Omarama and Otematata were attending, and the vehicle appeared to be off the road.
St John were called and around 1.30pm were still at the scene, treating one patient "in a minor condition".
Traffic was down to one lane, and traffic control was in place, the Fenz spokeswoman said.