Cadaver dogs have searched a water tank and a recently cemented outhouse at a property owned by Gus Lamont’s family.

The four-year-old boy was last seen playing at his grandparents’ Oak Park Station homestead near Yunta in outback South Australia on September 27.

Earlier this month, South Australian Police declared someone living at the remote station was a suspect in Gus’ disappearance and likely death.

On Tuesday, officers and cadaver dogs brought in from New South Wales inspected a water tank and an outhouse at a sheep station owned by Gus’ family located 30km west of Oak Park Station.

The search at one point focused on the outhouse, where fresh cement had recently been laid, the ABC reported.

They then moved to a second property at Grampus, about 24km from Oak Park, where Task Force Horizon detectives were seen scouring the homestead and surrounding areas.

Police announced this week that detectives had returned to the area to continue searching for evidence, adding they would there for at least two days.

No evidence relating to the boy’s disappearance has yet been found during the latest search.

Gus Lamont was last seen playing at his grandparents' Oak Park Station homestead near Yunta in outback South Australia

Gus Lamont was last seen playing at his grandparents’ Oak Park Station homestead near Yunta in outback South Australia

On February 5, South Australian Police declared someone living at the remote station was a suspect in Gus' disappearance and likely death

On February 5, South Australian Police declared someone living at the remote station was a suspect in Gus’ disappearance and likely death

Police returned to the region this week to launch a renewed search for evidence

Police returned to the region this week to launch a renewed search for evidence

Police said Gus’ grandparents, his mother and his younger brother were at Oak Park Station when he disappeared, but stressed his parents were not suspects.

On Monday, police arrested and charged Gus’s grandmother, 75-year-old Josie Murray, with firearm offences.

Murray was bailed to appear in Peterborough Magistrates Court in May.

Acting Officer in Charge of Major Crime Investigation Branch Detective Inspector Andrew Macrae said that the charges are not related to Gus’ disappearance.

He added that the charges were also not connected to an incident with a journalist who attended the property in October 2025.

Gus went missing from the 60,000ha Oak Park Station on September 27 last year and, despite the largest police search operation in the state’s history, no trace of him has been found.

No arrests have been made or charges laid over Gus’ disappearance.

Gus’ grandparents Shannon and Josie Murray have both enlisted the services of high-profile Adelaide defence lawyers.

Gus' grandmother Josie Murray (pictured with police) was arrested and charged with firearm offences on Monday. The charges are not related to the boy's disappearance

Gus’ grandmother Josie Murray (pictured with police) was arrested and charged with firearm offences on Monday. The charges are not related to the boy’s disappearance

Authorities on Monday began a two-day search at the remote station where he vanished in September (pictured in October)

Authorities on Monday began a two-day search at the remote station where he vanished in September (pictured in October)

Gus disappeared from Oak Park Station (pictured) on September 27

Gus disappeared from Oak Park Station (pictured) on September 27

They said they were ‘devastated’ by the police announcement and insisted they were still cooperating with the investigation.

There is no suggestion that Josie or Shannon Murray were involved in Gus’ disappearance.

Police have not said either is a suspect and it is not uncommon for witnesses in criminal cases to seek legal advice.

In November, a search of six uncovered and unfenced mine shafts located between 5.5km and 12km from the homestead lasted three days.

‘The inspection of the mine shafts … did not locate any evidence to assist in the investigation into Gus’ disappearance,’ a police statement said.

‘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.’

Before that, authorities drained a dam in late October, ruling out the possibility Gus had drowned.

It took police about three-and-a-half hours to drain 3.2million litres of water from the 4.5metre-deep dam, which is 600metres from the homestead.

The initial search for Gus included survival experts, SES crews, local trackers, multiple air support units and mounted police.

Aerial imaging within a 10km radius of the homestead had also been done.