Police searching for missing four-year-old Gus Lamont have not ruled out returning to the remote property where he was last seen just over seven months ago. 

Gus disappeared from his grandparents' Oak Park Station near Yunta, 300km north of Adelaide, while playing on a mound of dirt on September 27. 

Police declared his disappearance a major crime investigation in February, but despite extensive searches, no trace of Gus has ever been found. 

In a further blow for the little boy's loved ones, South Australian Police (SAPOL) said on Monday they had no new information. 

'This is one of those tragic stories that we would like to be able to provide more clarity to,' Commissioner Grant Stevens told a press conference. 

'But we don't have any further updates at this point in time. The taskforce operating within Major Crime Investigation Branch are continuing their work.

'I've not had a specific update in regard to their activities for the last couple of weeks.'

Commissioner Stevens added that officers plan to return to the home near Yunta 'at some time in the future', but provided no indication of when that would be. 

Police have previously said the operation has been the 'largest and most intensive' missing person search ever undertaken by the force.

In February, authorities announced they believed Gus was dead and that they had identified a suspect within his family. 

They later confirmed they found 'inconsistencies' in statements and timelines provided by some family members.

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

It has been stressed that his parents, Joshua Lamont and Jessica Murray, have been ruled out as possible suspects and are cooperating with the investigation.

Gus's grandparents, Shannon and Josie Murray, later retained separate lawyers, a move that is not unusual in these circumstances.

Both of the grandparents said they were 'devastated' by the police announcement and insisted they were still cooperating with the investigation.

Gus's parents, though separated, issued a united statement in February describing how their lives had been shattered by their son's disappearance.

'Every moment without him is unbearable,' they said. 'We know someone out there may have information.

'If someone knows what happened, we are pleading with that person - or anyone who may have seen or heard anything - to please come forward. Even the smallest detail could give us the answers we so desperately need.

They also thanked their supporters.  

'Your kindness has helped carry us through the darkest days of our lives,' they said.

'All we want is to bring Gus home and understand what happened to our beautiful boy.'

A month later, in March, police visited the remote Oak Park Station in a sweep for evidence but left with no new leads as to Gus's whereabouts.

In November, a search party found unfenced mine shafts located between 5.5km and 12km from the homestead near Yunta. 

'The inspection of the mine shafts... did not locate any evidence to assist in the investigation into Gus's disappearance,' police said at the time. 

'Several of the shafts were relatively shallow and could be visually inspected but the remainder were up to 20metres 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.

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