The 22-year-old man who died, Rutger Hale, of Auckland, was hit by an unknown object that crashed through the windscreen of his Subaru station wagon and appears to have exited through the rear windscreen.
Detective Sergeant Brian Cameron told a press conference in Wanaka yesterday of the actions of Mr Hale's partner, Danielle, after he was fatally injured.
''She has had to take control of the vehicle, grabbing ... the steering wheel whilst attempting to lift the driver's foot from the accelerator.
''She's done a remarkable job of steering the vehicle to its final resting place without being involved in a secondary crash.''
Danielle, who Mr Hale called Deezy Dee, was in the front passenger seat when she made the split-second move to take control of the car. She was uninjured in the accident.
Mr Hale, who was working as a farmhand, and Danielle had been staying at the Lake Hawea Holiday Park.
Mr Hale was from the small West Coast town of Moana, but later moved to Auckland with his family and attended Lynfield College.
Mr Hale's last Facebook message said he was ''back down to the dirty south'' with his 26-year-old Alaskan girlfriend, who had bought the Subaru they were travelling in just five weeks before the fatal crash.
His girlfriend was also able to tell police of a white four-wheel-drive utility in the area at the time of the incident.
Police interviewed the drivers of about 55 cars near the scene of the incident yesterday morning and Det Sgt Cameron said ''at least one'' person had approached police to say they were the owner or driver of a white utility that used the road and one person was being interviewed.
''It's not known at this stage if it is the white utility we are interested in or not.''
Police have yet to determine what the object was that struck Mr Hale.
Det Sgt Cameron said the hole in the Subaru's windscreen was described by one of those first on the scene as ''fist-sized''.
''Clearly there has been some contact with the interior of the vehicle as it has travelled through and exited through the rear window, which has been smashed in its entirety.''
While police were keeping an open mind on the cause of Mr Hale's death, nothing had been found to indicate premeditation.
''While this is a mysterious incident, it is not a suspicious incident.''
Asked if Mr Hale might have been hit by a bullet, Det Sgt Cameron said that was ''an extremely unlikely scenario''.
A pathologist carried out a postmortem examination yesterday afternoon and a team from the Institute of Environmental Science and Research, in conjunction with the Serious Crash Unit and Vehicle Testing New Zealand, was due to examine the car this morning.
Results from the postmortem and any further information were not likely to be available over the next few days, Det Sgt Cameron said.
