More than half a century after the disappearance of the Beaumont children from Glenelg Beach, new information has surfaced, prompting renewed focus on one of Australia’s most enduring mysteries. 

The disappearance of Jane, Arna, and Grant Beaumont on Australia Day in 1966 remains unsolved and their remains have never been recovered.

A private investigator, Bill Hayes, a former South Australian Major Crime Detective, has revealed that a new witness has come forward following a recent search at a North Plympton site. 

This site was once owned by factory boss Harry Phipps, who has been a suspect in the abduction. 

While the dig yielded no physical evidence, it spurred a woman to share her account.

The woman alleges she was abused by Phipps, an associate of her family, and that he had made claims to others about the children being buried at the old factory site. 

“It was extremely distressing, it still is,” Hayes said.

The new information, detailed in an update to a book about the Beaumont case authored by Hayes and Stuart Mullins, is considered credible by the two authors, who say the woman passed a lie detector test. 

“You knew she wasn’t making it up, you cannot make something up like she was telling us,” Mullins said.

The recent search at the North Plympton site was organised by Hayes and Mullins. 

Despite previous police digs at the location in 2013 and 2018 also proving fruitless, Mullins still believes that’s where the children are. 

“We still believe they were buried there … and it’s like as Bill said, where we were digging, you could only be 30 centimetres off,” he said.

While further digs at the Castalloy Factory are not possible due to plans for a housing development, investigators say their search for the truth continues elsewhere.