The four young people found dead in remote central Australia after their car broke down likely died due to heat and a lack of food and water, Northern Territory police say.
The body of a 19-year-old man and woman and a three-year-old boy were found on Wednesday after a man from the Willowra Aboriginal community, 300km north-west of Alice Springs, raised the alarm.
Police searching for a missing 12-year-old boy also believed to be in the car found the body of a child 120 metres from the three family members on Thursday, but he is yet to be formally identified.
The four are all believed to be related to each other but their names have not been released.
Southern Desert Division Superintendent Jody Nobbs described the event as a "tragic situation".
The group had left Willowra on Friday bound for the Jarra Jarra outstation and were last seen at Ti Tree, he said.
It is believed the car, which was unroadworthy, ran out of fuel with a flat tyre that day on the Jarra Jarra Road.
The temperatures were around 40C on Friday and the weekend.
The road is remote with limited traffic and it was likely the group did not see any cars before they perished, Supt Nobbs told reporters.
"The likely cause of death is succumbing to the elements," he said.
The bodies and car were about 60km from Willowra and 18km from Jarra Jarra, which would have been the nearest water source.
A land and air search was called off on Friday morning when police concluded there had been no more passengers.