
One person was in a white van travelling towards Luggate from Wanaka left the road at an 85kmh sign and come to a stop at the entrance to Lake McKay Station.
The accident was reported to police about 4.20am.
Police were unable to confirm the nature of any injuries at this time.
A detour is in place for traffic travelling between Wanaka and Luggate.
The detour is via Hawea Flat. Contractors are controlling the diversions at Mt Iron corner and at Luggate.
The highway should be reopen around noon, police said.
One vehicle was involved.