Heat on searchers for little boy lost in outback

The second day of a renewed outback search for missing four-year-old boy Gus Lamont has failed to find new evidence.

More than 100 search team members, including SA Police, Defence Force personnel and State Emergency Service volunteers, have each been walking 20-25km a day in hot, harsh conditions.​

With temperatures of 36C and strong northerly winds expected in the expanded area on Thursday, searching is expected to start at sunrise and end at midday.

​Police announced this week they had set up Taskforce Horizon to investigate the disappearance of Gus, who went missing at the Oak Park Station homestead about 40km south of Yunta, in SA's Mid North region, on September 27.

The initial search, which covered about 470 sq km, ended about a week after the boy went missing.

SA Police Commissioner Grant Stevens has said there was no evidence Gus was a victim of foul play and the task force was aimed at expanding the search area around the property.

Taskforce Horizon is made up of 12 specialists, who will analyse information from the search and provide advice.

"Search co-ordinator specialists, medical specialists and survivability specialists, looking at every possibility, and this is us exhausting those possibilities," Mr Stevens said.

Described as shy and adventurous, Gus was last seen by his grandmother, playing on a mound of dirt at 5pm on the day he disappeared.