Adelaide, Australia (CNN)Experts in the Australian city of Adelaide started excavating an industrial site Friday for the remains of three children who went missing 52 years ago.
Police start digging at site for 3 children missing for 52 years
Nine-year-old Jane Beaumont, her sister 7-year-old sister, Arnna, and their 4-year-old brother Grant, vanished after going to nearby Glenelg beach for a swim on a warm summer day on January 26, 1966.
Their disappearance is one of the country's most infamous cold cases, and one that police are desperate to solve to bring peace to the children's frail parents who are now aged in their 90s.
Friday's excavation is taking place at the Castalloy factory in North Plympton, in Adelaide's inner west, which was once owned by businessman Harry Phipps. He died in 2004.
Phipps came to police attention in 2007 when a book was published that suggested he might be a credible suspect, but was not taken seriously until two men came forward claiming to have been paid by Phipps to dig a trench at his factory site as teenagers.
Detective Superintendent Des Bray said police had previously searched the property in 2013, based on the information provided by the two men, but found nothing.
"It's clear that the two men did dig a hole. There's never been anything to prove that the Beaumont children are in the hole," said Bray, as he announced plans for the new excavation.
"Commonsense says if there's the slightest chance that the hole could be relevant we should search and that's what we're doing," he added.
By midday Friday, authorities had dug about one meter (3.3 feet) deep and were about 80 centimeters away from the anomaly that was initially detected, Detective Inspector Greg Hutchins told reporters.
Some animal bones have been found during the excavation, police said.
January 26, 1966 began like most others for the three young children of the Beaumont family. It was warm and Jane, Arnna and Grant begged their mother, Nancy, to go to the beach for a swim.
The children had made the same trip the day before so their mother gave them some coins for the bus fare and lunch, and instructions to be home by 2 p.m., according to news reports at the time.
Witnesses said they saw the children at the beach playing in the sand among the thousands who gathered to celebrate Australia Day.
They bought lunch at Wenzels cake shop on Moseley Road with a £1 note, even though their mother had only given them coins, and they were seen once more walking hand-in-hand down Jetty Road by a postman who knew them.
What happened next, no one knows for sure.
Witnesses would later claim to have seen the children in the company of a man on the foreshore at Glenelg, a beach about 20 minutes from the city center.
When the children hadn't returned by 7.30 p.m. their parents, Jim and Nancy Beaumont, called the police and a search began that would eventually involve hundreds of officers.
Frank Pangello was only a child at the time but went on to cover new developments in the case for five decades, first as a newspaper reporter and then as a television reporter for Channel 7.
"I was 12 years old then and I remember it vividly to this day," Pangello said. "In those days, in 1966, as kids it was quite an innocent period. It wasn't uncommon for young kids to go to the beach on their own without their parents."
"Initially it was believed that the kids were gone walkabout, that they had run away or they were with somebody. The police didn't treat it as a kidnapping or something sinister, they felt the kids would turn up in a day or so. After a few days, it was clear that it wasn't."
As public interest in the case grew, a torrent of false leads and misinformation flowed from a concerned public, throwing investigators off.
In one now notorious incident, a Dutch psychic traveled to Adelaide to help find the children and turned up nothing. In another, a 14-year-old sent fake letters to the parents, claiming to be from their daughter Jane saying that a man had abducted them.
Harbors would be drained and foreign countries would be visited in the search for the Beaumont children, but nothing turned up that was conclusive.
"We've had hundreds of people nominated as a person of interest and some of the most notorious and vile criminals across the country nominated as suspects. Similarly, in those cases, we haven't been able to prove they are responsible or exclude them. There's probably about a dozen people that fit into that category," Detective Superintendent Bray said.
Jim and Nancy Beaumont remained at their Somerton Park home for many years in the hope their children would return. Nancy even preserved their bedroom exactly as it was the day they disappeared, according to Pangello.
Phipps was first identified as a potential suspect by his son Haydn, who claimed to have seen the three Beaumont children in his backyard as a 16-year-old.
"Harry [Phipps] wasn't the archetypical predator," Pangello said. "He was a well-to-do man. Had a lot of respect in the community, ran a successful business and was a captain of industry. There wouldn't have been any reason for him to be a suspect."
His house was only 250 meters away from where the trio were last seen alive and the physical appearance of Phipps matched the description given by other witnesses who had claimed to have seen the children in the company of a tall man in his late thirties with "fair to light brown hair", a tan, medium build and a thin face.
The latest breakthrough came when a forensics team from Flinders University working with local television station Channel 7 revisited the Castalloy factory to re-examine the site with ground penetrating radar and found an "anomaly" that matched the size of the hole dug by the two men.
Unknown to the police who conducted the initial excavation of the site, the layout of the property had changed over the years.
While this is the strongest lead in the case yet, police are trying to temper expectations.
"We don't know what we will find," Bray said. More than anything, they want answers.