A double fatal road accident in South Canterbury's Waimate District went unnoticed for more than eight hours, until an injured person was found on the road.
The police say the crash, on State Highway 82 at Waihao Downs, is believed to have happened late on Saturday night but not discovered until about 8am Sunday.
The two who died are believed to be a 21-year old man and an 18-year old woman.
They were not wearing seatbelts, and it appears their vehicle failed to take what police describe as an easy left hand bend.
They say speed and alcohol probably contributed to the crash.