The three people killed in yesterday's crash between a car and a logging truck in South Waikato were American citizens.
The woman driver of the car and a man and a woman in the back seat died at the scene of the crash on State Highway One near Tokoroa.
Police said they were not wearing seatbelts.
A fourth occupant in the car who was critically hurt is also an American.
Police said the car was on the wrong side of the road before it collided with the logging truck but they don't know why.
There have been a series of recent crashes involving overseas drivers from right-hand-drive countries.
The investigation into the cause of the crash is continuing.