Blistering heat has paused the South Australian search for four-year-old August “Gus” Lamont on Thursday.

Nineteen days have now passed since Gus vanished from his grandparents’ remote sheep station near Yunta, with personnel from police and Australian Defence Force returning to the property on Monday — this time with a new strategy, new search zones, and a new taskforce.

Gus was last seen playing on a mound of dirt just 500m from the homestead about 5pm on September 27.

When his grandmother called him in half an hour later, he was gone, with police believing the four-year-old had simply “wandered off”.

Search efforts on Thursday were paused as the outback heat was nearly 40C, with the search to resume Friday morning before it is expected to scale back once again.

Only a single boot print remains as the only clue to Gus’s disappearance.

It comes as new details surface about what the missing boy’s family were doing when he vanished.

Gus was outside playing in a nearby dirt mound beside the family home.

Gus’s grandmother was inside during that time watching his little brother, Ronnie, 7NEWS understands.

The boy’s mother and his other grandparent were 10km away, tending to the station’s sheep.

The boy’s father was not on the property at the time.

Gus’s grandmother discovered the boy missing when she went to call him inside about 5.30pm.

Family called police to report the boy missing three hours later.

Hundreds of square kilometres of the property’s 60,000ha have been scoured by foot, vehicle, drone and helicopter over the past two and a half weeks.

But despite the scale of the operation, no further clues have been found.

Police have said there is no evidence at this stage to suggest any foul play.

Source: https://7news.com.au/news/gua-lamont-search-new-details-emerge-of-missing-boys-last-night-with-family-c-20365163