The body of a child has been found following an extensive land and air search in a remote part of Central Australia.

Key points: Fourth body located following land and air search in Willowra

Fourth body located following land and air search in Willowra Child's body found 120 metres from young family found dead on Wednesday

Child's body found 120 metres from young family found dead on Wednesday Police cannot confirm if it is that of a missing 12-year-old boy

Police said the child's body was located 120 metres away from a family of three who were found dead on Wednesday near an abandoned car on the outskirts of the community of Willowra, 300 kilometres north-west of Alice Springs.

The bodies of a young family — a 19-year-old man, a 19-year-old woman and a three-year-old boy — were found on Wednesday about 4.5 kilometres from their broken-down vehicle.

On Thursday morning, police said a 12-year-old boy, who they believed was with the group, was not found among the dead.

Following an extensive land and air search in the Willowra area, a child's body was found on Thursday afternoon.

"A formal identification of the child is yet to be undertaken and as such, police are unable to confirm it is the body of the 12-year-old boy," NT Police said in a statement on Thursday.

"The body of the child was located 120 metres from the family, found dead on Jarra Jarra Road yesterday."

Duty Superintendent Shaun Gill said the child is yet to be identified, but police have ruled out the possibility that anyone else was in the car.

"The search continued for a couple of hours afterwards, just to make sure there was no-one in area missing that we weren't aware of," he said.

At about 6:00pm last night the search was called off.

Family may have perished in heat

NT Police were alerted to the deaths, which were not believed to be suspicious, when a person walked into a local health clinic and raised the alarm just after midday on Wednesday.

Superintendent Jody Nobbs said the deceased were last seen leaving the community of Willowra on November 2.

He said they were heading towards Jarra Jarra community, 18 kilometres from where their vehicle was found.

The three bodies discovered on Wednesday were those of a young family, but police have not said if the 12-year-old boy, who was the subject of land and air searches, was also related.

Remnants of food and water were found in the car, and earlier on Thursday, police said the family may have walked away from the vehicle in "extreme weather" and become "caught out".

It is not known how the car broke down or when it likely broke down.

On Saturday, Daniel Price died on an isolated track near the Gibb River Road, in the Kimberley.

On October 27, a 27-year-old man died during a hike in Western Australia's mid-west region.