Work has begun to excavate a site previously owned by a person of interest in the disappearance of three children almost 60 years ago.
Organisers hope the dig will provide answers to one of Australia's greatest unsolved mysteries.
They say there is significant circumstantial evidence that Harry Phipps kidnapped, murdered and buried the three young children of Jim and Nancy Beaumont at his Castalloy foundry in suburban Adelaide in January 1966.
Independent MP Frank Pangallo was joined at the site in North Plympton on Monday by forensic archaeologist Maciej Henneberg, author Stuart Mullins and former South Australian detective Bill Hayes.
Large earthmoving equipment began preliminary excavation work on the weekend at the northern end of the government-owned site, which is about to be sold for development.
Early on Monday, Professor Henneberg discounted the site of the original 2013 dig after the excavation team reached a depth of three metres, a spokesperson for Mr Pangallo said.
Attention then turned to the new dig site, where trees were removed on the weekend.
The excavation team has started removing about three metres of topsoil to reach the level the site was at in 1966, before excavating further.
The Beaumont children - Jane, 9, Arnna, 7, and Grant, 4 - vanished without trace during a seaside outing to Glenelg on Australia Day.
"The disappearance and likely murder of the Beaumont children is one of Australia's greatest unsolved mysteries and I hope this new search will bring some sort of closure to their long suffering families after nearly 60 years," Mr Pangallo said.
"If it doesn't, at least we know we have tried and can rule out that site once and for all.
"The new evidence indicates previous digs on the former Castalloy factory site didn't go deep enough - so that is the intention of the new search."
The search revisits two previously scoured areas along with a third new area, and is expected to take about a week.
Shortly after his death in 2004, Phipps' son Haydn revealed he had seen three children at the family home shortly after the disappearance.
Two brothers have also revealed they were paid by Phipps three days after the children disappeared to dig a "grave-size" hole on the then-factory site.
