Anomaly’ Detected at Possible Grave Site of Beaumont Children

A team of excavators will dig up a possible grave site at a South Australian factory where the bodies of the Beaumont children, missing for 52 years, could be buried.

Investigations into the 1966 disappearance of nine-year-old Jane, Arnna, seven, and four-year-old Grant have led detectives back to the factory they first excavated in 2013.

South Australia Police said they were lead back to the property after a “anomaly” was detected on the land by a team of researchers with Flinders University.

A fresh dig at the North Plympton site, which is now the Castalloy factory, will begin in the next few weeks, police said.

SA Police conducted an extensive search for the Beaumont children at the time of their disappearance.Police will dig up an area of land at a South Australia factory after obtaining new evidence. (9NEWS)

The area in question is approximately six square metres and is nearly three metres deep.

The land is believed to have been dug up by two boys who worked for deceased businessman Harry Phipps at the factory the same year the three children went missing.

More than 50 years later, the men are now helping police with their investigation.

“There is a need to temper expectations, we don’t know what we’ll find,” Detective Superintendent Des Bray told reporters today.

“But that site warrants further investigation because it does appear to be a hole.

Jane 9, Arnna, 7, and Grant, 4, have not been seen in 52 years.

“Like everyone in the community, we are desperate to have this case solved and to provide answers to the family.”

Police first dug for evidence at the factory in 2013 after details of the theory were published in a book titled The Satin Man.

The book outlined a case against a man, later identified as Mr Phipps, who was referred to as the “Satin Man” due to his apparent fetish for wearing satin clothing.

One of the book’s authors, Alan Whiticker, said Mr Phipps’ own son accused him of killing the three children.

A previous dig at the site in 2013 did not find any evidence. (9NEWS)

An author of the book "The Satin Man" said Harry Phipps' son believes his father killed the Beaumont children.

“The (Satin man’s) son came forward to us and said he did see the Beaumont children the day they disappeared,” Mr Whiticker told 9NEWS in 2016.

“They came into the backyard of the family home, which is no more than 500 metres from where they were last seen.”

Police today said Mr Phipps was still a person of interest but there is not enough evidence to categorise him as a suspect.

Harry Phipps became known as the "Satin Man". (9NEWS)

“Harry is still a person of interest and we are committed last year to reassess everything that has been done,” Det. Supt Bray said.

In an exclusive interview, 9NEWS spoke with a former classmate of one of the victims, who says she’s hopeful closure is near.

Averil Hodge still remembers posing for school photographs just metres from her close friend Jane.

“We lived in an age of innocence then,” Ms Hodge told 9NEWS.

“I remember her riding her bike to my home. And we’d play in the backyard. Or we’d got to the beach. We used to have fun.”

Ms Hodge remembers the concern on the faces of her teachers, along with the anxious and scared kids around her when the siblings went missing.

She said she got goosebumps yesterday when she learned police would be pursuing a new lead.

When police searched there unsuccessfully in 2013, they were questioned as to why they dug in one small area and were accused of ignoring information from the two men who claimed to have dug the hole.

The state government has offered a $1 million reward for information leading to an arrest and conviction or the discovery of the victims’ remains.