Police said two cars crashed on the road between Queenstown and Wanaka about 2.40pm.
One person was trapped in a vehicle, they said.
The Otago Regional Rescue helicopter was called to the scene but in the end was not needed.
Two people, one with moderate injuries and another with minor injuries, were taken to Lakes District Hospital by ambulance.
Motorists are asked to avoid the area.
Emergency services were at the scene and motorists were being advised at about 3.30pm of a delay of an hour to an hour and a half.
Hundreds of motorists chose to turn back, and take another route between Wanaka and Queenstown.