When British backpackers Caroline Clarke and Joanne Walters were found brutally murdered in the Belanglo state forest in September 1992, the Sun ran the headline: “Beast of the bush: Brit girls victims of Oz serial killer.” The newspaper speculated that the killer “could be a fiend responsible for the disappearance of 20 people in the area over 20 years”.

Ivan Milat, who has died of cancer aged 74, was convicted in 1996 of the murder of seven people, aged 19 to 22, who disappeared while hitchhiking south of Sydney. But his death means his suspected involvement in several other disappearances may never be resolved.

Ivan Milat, Australia's most notorious serial killer, dies aged 74 Read more

The backpacker killings became the subject of intense international media scrutiny and speculation after the discovery of seven victims’ bodies in makeshift graves in 1992 and 1993.

In the intervening years, Milat and the cold brutality of his crimes have held an enduring grip on the Australian psyche, and Belanglo has become a byword for horror. As the journalists Mark Whittaker and Les Kennedy wrote in their book about the case, Sins of the Brother, published in 1998, it was “a peculiarly Australian story”. The callous murders by the tanned, muscle-bound Australian with the Dennis Lillee moustache seemed to reveal something uncomfortable about the nation’s character.

With his death comes an unsatisfying sense of things still unresolved. Milat was one of six prime suspects in the cases of three women – Leanne Goodall, Robyn Hickie and Amanda Robinson – who all went missing near Newcastle, north of Sydney, near where he often worked as a road worker, within four months of each other between 1978 and 1979.

Facebook Twitter Pinterest Serial backpacker murderer Ivan Milat. Photograph: AAP

In 2002 Milat was called to give evidence at a coronial inquiry into their disappearances but no charges were laid.

The possibility that Milat did not act alone has been the subject of endless speculation. During his trial Milat’s lawyers attempted to place blame on one his brothers, and police actively investigated the possibility of an accomplice. In his sentencing remarks, Justice David Hunt said it was clear that in at least two of the killings two people had been involved.

An avid shooter and hunter

Ivan Robert Marko Milat was born on 27 December 1945, the fifth of 14 siblings and one of 10 brothers. From the outside, the early years of his life were unremarkable in postwar Australia.

Facebook Twitter Pinterest Detectives take Milat into custody after raiding his home in Eagle Vale, Sydney, in May 1994. Photograph: Fairfax via Getty Images

His father worked on the wharves in Sydney after migrating from Croatia after the first world war, while his devoted mother cared for the children. His father, a strict disciplinarian, eventually started a tomato plantation at the family property in Moorebank, western Sydney, where his sons were put to work.

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Neighbours have described the family as insular, and the young Milat did not stand out among his siblings. But as they grew older, the hold of his parents slipped. Petty theft and troublemaking graduated to break-and-enters and burglary. Seven of the 10 brothers have had run-ins with the law, and the Milat family became well known to police.

Ivan Milat leaned into the lifestyle. In the 1960s, during his late teens and early 20s, he served increasingly long stints in jail for a series of break-and-enters and burglary. A fan of fast cars and Brylcreem, with a quiet charm and fastidious nature, he found time to have affairs with two of his brothers’ girlfriends in the same period.

As Milat got older he was linked to crimes of increasing severity. In the 1970s he was tried but acquitted of raping 18-year-old Margaret Patterson, who had been hitchhiking to Melbourne with a friend.

As Whittaker and Kennedy wrote in their book, Milat often bragged to friends about his capacity for violence. In one instance recounted in the book, he described to an acquaintance how to turn a person into “a head on a stick” by stabbing them in the spine. He was an avid shooter and often hunted in the forest where the bodies of his victims were found.

Facebook Twitter Pinterest Ivan Milat often bragged to friends about his capacity for violence

The crimes for which Milat served his sentence began in December 1989. On the day before New Year’s Eve, Deborah Everist and James Gibson, from Melbourne, set off from Sydney towards Albury, near the border of New South Wales and Victoria, for an alternative lifestyle festival.

They had planned to meet friends, but never arrived. When neither made contact with family in the weeks following, their relatives filed a missing person’s report. Police were not immediately concerned.

The other five victims followed similar paths. Simone Schmidl, 21, from Germany, left Sydney for Melbourne on 20 January 1991. She had been due to meet her mother at Melbourne airport four days later. Gabor Neugebauer, 21, and Anja Habschied, 20, also German, left Sydney on Boxing Day 1991. The couple were supposed to be making the 4,000km trek to Darwin before returning to Munich a month later. They never got on the plane.

Facebook Twitter Pinterest Milat’s known murder victims. Top, from left: Deborah Everist, Australia; Anja Habschied, Germany; and Simone Schmidl, Germany. Bottom, from left: Joanne Walters, UK; Gabor Neugebauer, Germany; Caroline Clarke, UK; and James Gibson, Australia. Photograph: Reuters

Clarke, 21, from Surrey, and Walters, 22, from Maesteg in Wales, met at a backpackers’ hostel in Sydney’s Kings Cross and shared a flat there. They had hitchhiked together a number of times in Australia; to the small town of Mildura in Victoria and on the way to Tasmania to pick fruit. In April 1992 they left Sydney again, with vague plans that seemed to involve heading south towards Victoria, or to Perth in Western Australia.

When weeks passed without any contact with their parents, the two families sprang into action, alerting police in the UK and Australia and using the media to drum up interest in the case.

It didn’t take long for journalists to start linking their disappearance with other cases. In April 1992 an Australian television program followed Neugebauer’s parents as they searched for their son, pointing to other missing backpackers.

But it wasn’t until September 1992, when two runners discovered the first of the bodies – Clarke and Walters – that the severity of the crimes began to emerge. Walters had been stabbed 21 times in the back and 14 times in the chest. Her spine had been severed by one vicious blow. Lying in scrub 10 metres away, Clarke had been shot 10 times in the head while blindfolded and stabbed in the chest.

The grisly discoveries didn’t end there. A year later, in October 1993, a bushman collecting firewood found another body – it was James Gibson. Police found Everist nearby. A month later the three Germans were discovered. Like Clarke and Walters, all had been viciously murdered.

‘That’s what the Milats do’

After an intensive investigation, police narrowed down the list of suspects to a few dozen, but it was another Briton, Paul Onions, who provided the crucial piece of evidence.

Facebook Twitter Pinterest The key witness Paul Onions, who flew to Australia from the UK to give evidence against Ivan Milat. Photograph: Mark Baker/Reuters

Onions had managed to escape from Milat’s vehicle in early 1990, and flew back to Australia during the investigation into the murders to identify him.

In January 1990, three weeks after Everist and Gibson disappeared, Onions had hitched a ride to Canberra with a moustachioed man he would later describe as looking like the Australian cricketer Dennis Lillee.

The trip began uneventfully but, as they made their way down the highway, Onions became unsettled by the questions the man, who gave his name as Bill, was asking: Did anyone know where he was headed? Was anyone waiting for him in Canberra? Had he done any special forces training in the navy?

As the car approached the Belanglo state forest, the driver pulled to the side of the road saying he wanted to find some cassettes to play. Instead, he produced a gun and a length of rope, telling Onions: “This is a robbery.” The backpacker made a run for it. The two fought and the man fired a shot before Onions managed to flag down a car and escape.

He filed a report with police, who told him it was unlikely they would find the man responsible. But six years later Onions’ testimony would be crucial to Milat’s conviction. When police searched Milat’s house in south-western Sydney in connection with the Onions robbery, they found items belonging to his victims. More belongings were discovered with his relatives.

Milat was arrested in 1994 and convicted in 1996 after an 18-week trial. He was held in a high-security unit at Goulburn Supermax – home to Australia’s most dangerous criminals. In May he was transferred to Long Bay in Sydney after he was diagnosed with terminal oesophagus and stomach cancer. During his time in solitary confinement at Goulburn, he had been on several hunger strikes and sometimes swallowed sharp objects if guards did not meet his demands.

The legacy of the Milat murders has endured. In 2012 Milat’s great-nephew, Matthew Milat, was sentenced to at least 30 years in prison for the axe murder of a friend in the same forest. The court heard he had later gloated about the murder, saying: “That’s what the Milats do.”

Facebook Twitter Pinterest Matthew Milat, the great-nephew of serial killer Ivan Milat, was sentenced to 43 years’ jail with a non-parole period of 30 years for the murder of David Auchterlonie. Photograph: Tracey Nearmy/AAP

Many of those linked to the backpacker murders had held out hope that Ivan Milat would reveal more about his crimes before his death. In October, Caroline’s Clarke’s father, Ian Clarke, told a reporter he still hoped for a deathbed confession.

“We still think of Caroline every day but it doesn’t mean to say we have to think of Milat every day,” Clarke told the Australian Associated Press from his home in Northumberland.

“If he was to finally face up to the fact and admit to any others that he has done, if indeed he has, then I think that would be a wonderful thing for those parents, because for the short time that we didn’t know, I know just how they must be feeling.”

It was not to be.

