By Jessica Haynes, ABC

Australian police have released a photo of missing four-year-old boy Gus.

Australian police have released a photo of missing four-year-old boy Gus.
Photo: SAPOL / SUPPLIED

It is every parent’s worst nightmare.

A small child, playing happily outside his home in South Australia’s mid-north, wanders off into the bush.

On a Saturday afternoon, Gus was last seen “playing in the sand like he normally does”, shovel in hand, wearing a sun hat, blue shirt, long grey pants and boots.

About 5pm, Gus’s grandmother discovered the “adventurous” four-year-old was missing, sparking a more-than-week-long search in challenging conditions.

Vast expanse

Many would struggle to comprehend the size of the sheep grazing property where Gus is missing.

Community members say they are holding on to the hope that Gus will be found alive. (ABC News: Justin Hewitson)

Community members are holding on to the hope Gus will be found alive.
Photo: Supplied / ABC News

The property is 6000 hectares – or 60 sq km – and spans a complex mix of terrain.

The isolated homestead is about 40km south of Yunta, which has a population of 60 people, and is about 300km northeast of Adelaide. It is only reachable by dirt roads and, according to police, has six gates to get through to the property.

Police said the family began a desperate search at the property for three hours on Saturday, before calling authorities, who put up a helicopter with infrared technology, but to no avail.

On Sunday, police continued an extensive ground search using trail bikes, ATVs and a drone, scouring a 2.5km radius from where Gus was last seen.

Calls to State Emergency Service volunteers were made to join the search and, by Monday, water operations began to search dams and tanks on the property.

When the ABC arrived at the scene on Monday, reporter Bethanie Alderson said the terrain was deceptively challenging.

“The enormity of the sheep station hits you as soon as you arrive, with blue bush scattering the red dirt as far as the eye can see,” she said. “The only sign of its end is the blue, rugged peaks on the horizon – the beginning of the Flinders Ranges.

The bushland near the homestead where Gus was last seen in outback South Australia.  (ABC News: Justin Hewitson

Bushland near the homestead, where Gus was last seen in outback South Australia.
Photo: Supplied / ABC News

“The arid scrubland is laced with winding sandy tracks, which reveal hidden crevices and dry creek beds at almost every turn.”

On Tuesday morning, SA Police Commissioner Grant Stevens described the conditions as “challenging” and said there were “lots of places a small child might find themselves, which would be hard for us to identify as easily as people may think”.

Later that day, Gus’s devastated family released a statement, read by family friend Bill Harbison.

“This has come as a shock to our family and friends, and we are struggling to comprehend what has happened,” he said. “Gus’s absence is felt in all of us and we miss him more than words can express.

“Our hearts are aching, and we are holding onto hope that he will be found and returned to us safely.”

Bill Harbison, a friend of Gus's family, said his disappearance came as a 'shock.'

Bill Harbison, a friend of Gus’s family, said his disappearance came as a “shock”.
Photo: Supplied / ABC News

The family also asked for privacy.

Search ramped up

On Tuesday afternoon, a footprint was found, the first and only clue since Gus’s disappearance.

Soon after, a man with specialist tracking skills and a “close connection to the land” was enlisted to join the search.

A footprint believed to belong to Gus was found during the search.

A footprint believed to belong to Gus was found during the search.
Photo: SAPOL / SUPPLIED

As the hours moved on throughout the week, more resources were thrown at the search, including community volunteers.

By Wednesday morning, police said they were preparing Gus’s family for the news that the search would soon enter a recovery phase.

“We always hold out hope that he’s a tough lad, and he’s crawled under a bush and he’s still alive, but we’re just preparing the family for the fact that we may be moving from a search effort to a recovery,” Superintendent Mark Syrus said.

The same day, 40 cadet police officers joined the search and major crime detectives arrived, but police were quick to say there was “no suggestion of anything suspicious”.

“As any part of any search, there’s an investigational process, so they’re just doing their due diligence,” Syrus said.

By Thursday, almost 50 Australian Defence Force personnel arrived to assist, but after nearly a week of searching, police announced they would scale back their efforts on Friday.

A tracker (pictured) has been called in to help in the search for missing four-year-old Gus on a rural property near Yunta. (ABC News: Daniel Taylor)

A tracker was called in to help in the search for missing four-year-old Gus on a rural property near Yunta.
Photo: ABC News / Daniel Taylor

Assistant Commissioner Ian Parrott said police hoped for a “miracle'” to find Gus alive and well, but had found no clues leading to his whereabouts.

“The search for Gus has probably been one of the largest, most intensive searches for a missing person conducted in South Australia in recent times,” Parrott said on Friday. “Unfortunately, at no point has there been any significant evidence that has enabled us to really focus in a direction for our search.”

He described Gus as an “adventurous and shy” child, with an “angelic face”, whose disappearance has been “upsetting” and “traumatic” for the family.

“Life is not supposed to work where a parent loses a child,” he said. “It’s supposed to work the other way around.”

Community efforts praised

At the heart of the search has been a community effort, which has included locals, friends and volunteers.

A food truck business from nearby Peterborough drove up during the week to provide sustenance to those assisting the search effort.

While the search has been buoyed by support of local community members and authorities from throughout the country, hopes of finding Gus have slipped away throughout the week.

Searchers had been covering about 30 kilometres of territory every day.

Searchers had been covering about 30km of territory every day.
Photo: SAPOL / SUPPLIED

Parrott praised the “unwavering commitment” of those who joined the search, especially the community that rallied around the family.

“That community spirit has really shone through this process, as has the outpouring of sympathy and acknowledgement from the broader community of South Australia,” he said.

While the police presence at the family homestead has grown quieter, Parrott said investigators were still pursuing ongoing lines of inquiry.

“[We] will not rest until we can try and find the answer to why Gus has gone missing.”

– ABC