Southern Desert Division Superintendent Jody Nobbs said police are yet to rule out that there may have been more passengers in the vehicle.
"Although police have no information that suggests there were other passengers in the car, we will continue a precautionary land and air search until we are satisfied that all areas of interest have been sufficiently canvassed," he said.
Police and community members had desperately been searching for the 12-year-old boy missing in remote Central Australia following the tragic death of the young family he was travelling with.
Remnants of water and food were found at the scene.
Family members informed police on Wednesday night that the 12-year-old boy had also been travelling with the young family when they departed from Willowra on Monday, November 5.
The vehicle and its occupants, destined for nearby Yarra Yarra, were not seen again until Wednesday afternoon.
Police initially responded to a report of a fatal motor vehicle crash before realising on arrival that it was a non-fatal, broken-down vehicle situation.
Supt Nobbs said the "distraught" man who initially raised the alarm at Willowra Health Clinic would be a critical part of the police investigation.
He said the tragic incident was a sad reminder to take precautions when travelling on remote Territory roads.
"This does serve, unfortunately, as a timely reminder for anyone travelling on NT roads to ensure that when you travel your vehicle is in a fit state, that you have sufficient supplies including water and a first aid kit, and that someone is aware of what your travel itinerary is — when you intend to leave, arrive and your anticipated routes," he said.
Police do not believe the family's deaths were suspicious but investigations are ongoing.
