Police say they have found no new evidence of missing four-year-old Gus Lamont as they conclude their fourth search for the boy today — a day earlier than previously planned.

SA Police returned to the family’s sheep station on Tuesday morning determined to find new evidence or rule out another location in the ongoing search for the missing boy, 61 days since he was last seen.

Police said this week’s search involved the inspection of six mine shafts, and several locations were identified following analysis of aerial mapping and imaging conducted following recent ground searches.

“The inspection of the mine shafts, located between 5.5km and 12km from the … homestead, did not locate any evidence to assist in the investigation into Gus’ disappearance,” police said in a statement on Wednesday afternoon.

A mine shaft in outback South Australia.

A mine shaft in outback South Australia where police have searched for Gus. (Supplied: SA Police)

“Several of the shafts were relatively shallow and could be visually inspected but the remainder were up to 20 metres deep and specialised equipment was required to complete the searches.”

Police said Gus’s family had been advised of the results of the renewed search and were being supported by a victim contact officer.

“There hasn’t been any evidence or information found during these searches, unfortunately, so we still don’t know where Gus is at this time,” Assistant Commissioner Philip Newitt told ABC’s SA Regional Drive program.

“We looked at several locations around there — we looked at some mine shafts and some other areas that cropped up on the aerial mapping and also areas that came out of the recent searches.”

Closeup of red dirt and rocks with small shrubs in the distance

Police have been searching remote bushland. (ABC News: Guido Salazar)

The assistant commissioner said the decision to focus on the mine sites came after “discussions with family”.

“We have to eliminate all potential areas,” he said.

“In something as tragic as these circumstances, whilst they are a long way from the homestead, these mines, up to 10, 12 kilometres — it’s still absolutely a path we need to go down just to ensure we’ve crossed every ‘t’ and dotted every ‘i’.

“Our interest is absolutely looking for any signs or prints or objects that are going to provide some clues.”

‘People are just upset’

The search has its own dedicated Task Force Horizon, which are at this time accompanied by STAR Group officers who are specialists in recovery missions.

Task Force Horizon officers have not ruled out returning to the property as the investigation continues.

As police announced the fourth search for missing Gus earlier this week, a flurry of journalists and cameras retraced the now well-traversed path to an outback town in South Australia.

For locals like café owner Phillip White in neighbouring Peterborough, around 85 kilometres south-west of Yunta, each time the search is renewed, a trickle of new faces is being brought into local hotels and cafes.

A man working a coffee machine at the counter in front of a kitchen and under a sign that says takeaway coffee order here

Peterborough café owner Phillip White says the community is distressed at the boy’s disappearance. (ABC News)

Mr White said the lack of answers was what most residents have found so upsetting, as it has for many people across the country who have been following the multiple search efforts.

“I just hope that something comes [of it], of any sort, because it’s been a couple of months and it’s a long time,”

Mr White said.

“I hope they find something because of the family.

“In a small community the whole community is a family and the main part is the family is upset. You’ve got to have an end.”

In contrast to searches in the early days after Gus’s disappearance, media has not been permitted on the property and no police spokesperson has been on the ground to answer reporters’ questions.

While it was difficult to picture the depths of the mine sites police have explored, a 30-minute drive north of Yunta reveals a glimpse into the town’s glory days of 19th-century gold mining with the faded relics of the Alma and Victoria mines.

At its peak, the Waukaringa site was the largest single gold mine in South Australia but today a dilapidated chimney and a labyrinth of underground tunnels and shafts are all that remain.

Brick walls of former remnants of a building on dry red dirt

The broader area around Yunta is dotted with old gold mining sites. (ABC News: Guido Salazar)

But for the local community, answers cannot come soon enough.

“It’s sort of a shock to have something like that happen … people are just upset,” Mr White said.

“People like a result, they’ve done so much trying to find him.”