The group’s leader, a violent standover man, was also adept at stealing cars and “rebirthing” them for sale to make extra cash.

But he also had a more sinister secret.

He was a ruthless killer, eliminating any perceived threat without remorse.

Police suspect he was responsible for five murders in a seven-year period in the 1990s — four in South Australia and one in Victoria — with at least two of them committed with his father.

Each of the murders — Leo Joseph Daly, 33, David Michael McWilliams, 40, Robert Stanley Pendergast, 32, Jaun Morgan, 15, and Victorian career criminal Aubrey Broughill, 73 — remain unsolved.

Their alleged killers, who cannot be identified for legal reasons, have remained out of reach of police in two states, simply because of lack of evidence.

One of the pair — whom the Sunday Mail will call the “Smiths’’ — is now in his mid-70s and lives at Renmark while his son, in his 50s, is in a Darwin prison awaiting trial on drug-trafficking charges.

The four unsolved SA murders are now the subject of renewed attention under Operation Persist, SAPOL’s cold-case murder initiative, while the Victorian murder remains an open cold case.

Since its inception almost three years ago, Operation Persist has resulted in arrests in six cold-case murders dating back 24 years.

Major Crime case officer Detective Senior Sergeant Mark McEachern said the case — dubbed Operation Jarrah — was one of the most difficult he had encountered in more than 30 years of policing.

“It’s frustrating because we just haven’t got enough evidence to charge anyone with any of the murders,’’ he said. “It’s because of the close-knit nature of the group and the fact no information got out.

“We worked intensively on this for a couple of years, initially, and have done more since, but still haven’t got the evidence to charge anyone.’’

Besides the lack of assistance from witnesses, the fact the bodies have not been found has also hampered the investigations severely.

While several members of the group had come to the attention of police in SA and Victoria in the late 1990s while they were investigating thefts from rural properties, it was the gang’s biggest job in Adelaide that would prove to be its undoing.

On July 7, 1998, four armed gang members donned overalls and balaclavas to hijack a truck as it drove through Torrensville, stealing its cargo of cigarettes — worth almost $500,000.

The robbery was one of Adelaide’s largest — and most audacious.

“The robbery itself was a massive investigation. It was unprecedented in Adelaide — a truck hijacking, hundreds of thousands of dollars worth of cigarettes taken by armed offenders,’’ Det. Sen. Sgt McEachern said.

“That alone to start with was an unusually serious robbery.’’

The truck was found burnt out later the same day, destroying any potential evidence. A large portion of the cigarettes was later found hidden on a property at Wool Bay, on Yorke Peninsula, and receiving charges were laid against an associate of those involved in the robbery.

Initial investigations into the hijacking were launched by detectives from Sturt CIB and the Smiths were identified as suspects.

Detectives had no idea their inquiry would soon be linked to four murders.

The investigation into the cigarette theft was in its early stages when they got the first hint.

Inquiries led them to a warehouse at Welland rented by a man named David McWilliams, 40, who could not be located.

Initially, detectives thought this was because he may have been in hiding following the heist but they would soon discover otherwise.

In another twist, it was while detectives were interviewing associates of McWilliams that they discovered another man, Leo Daly, 33, had been murdered several months earlier by the father and son who had emerged as the prime suspects in the robbery.

Detectives believe Daly, a petty criminal also involved in the drug world, was bashed in April, 1998, at Mitchell Park by the pair.

In an astonishing display of callousness, Daly was then taken to the sea off Cape Jervis, south of Adelaide, shot and dumped overboard.

The motive for his murder was apparently a $1000 drug debt he owed Smith Jr.

On June 16, 1999, detectives charged the Smiths with the murder of Daly. When they appeared in Adelaide Magistrates Court, both gave the appearance of everyday blokes — not hardened killers. Their time behind bars would be minimal.

Less than a fortnight later the charges against both were dropped because a key witness refused to give evidence. They have never been recharged.

“Unfortunately, that key witness declined to co-operate any further or to testify,’’ Det. Sen. Sgt McEachern said. “That was the catalyst for the matter being withdrawn because there was no prospect of a conviction without that witness.

“The witness was a person known to the group and things just got too difficult for that witness. There were fears about giving evidence.’’

It was while detectives continued investigating Daly’s murder and the cigarette truck heist that they received information McWilliams had also been murdered.

An informant revealed he had been killed by the suspected ringleader in the robbery — Smith Jr — because he was bragging about his involvement and was viewed as a liability.

Detectives have no firm information on either how he was killed or where his body may be, although searches were made of scrubland near Monarto, east of Adelaide, after vague intelligence on a possible gravesite.

While McWilliams was the last of the four local murders, detectives have no evidence to indicate he was involved in any of the three preceding deaths — but he may have had knowledge of Leo Daly’s case.

Incredibly, as investigations continued into the Daly and McWilliams’ murders, more information was received about a third murder of an associate of the group.

The associate, Robert Pendergast, had arrived in Adelaide in January, 1999, and was murdered a month later.

A known drug dealer, it is believed he was killed over a drug debt he claimed was owed to him by the group.

Information on how he was killed and where his body was disposed is scant.

While inquiries into those three murders continued, information was received about a fourth murder — 15-year-old Juan Morgan, in 1992, who was also connected to the group.

Very little information has been gleaned on why he was killed but it is believed he had a dispute with a gang member. Detectives believe Morgan was buried in scrubland on the SA/Victorian border. Somewhat sadly, Morgan was never reported as a missing person.

Det. Sen. Sgt McEachern said the common link in all four SA cases was Smith Jr, but his father may have only been involved in one of them — that of Leo Daly.

It is suspected, however, that he would have knowledge of each of them because of his close involvement with the group and its criminal activities.

It is more than likely the murders stopped because of the police attention following the cigarette robbery and the Smiths’ arrests on the Daly murder charges.

“By the time we got close enough to them, Daly and McWilliams had already disappeared,’’ he said.

“The disruption caused by our investigations stopped their activities.’’

Detectives believe, at most, there were four or five individuals in the group which was ruled with an iron fist by Smith Jr. And knowledge of the murders was confined to “relatively few’’ people in the group.

“That’s part of the reason why we have so little information about them,’’ Det. Sen. Sgt McEachern said.

“They were a very tight criminal group and that’s why I believe we have received so little information.’’

As is often the case in the criminal underworld, the paths of police in different jurisdictions cross as their individual investigations evolve.

Operation Jarrah had been running for some time when Victorian police closed in on five people who had been stealing property from farmhouses and charged them with the theft of more than $500,000 worth of farming equipment.

Among them were the two alleged ringleaders of the gang and another man — Melbourne career criminal Aubrey Broughill.

In his 70s, Broughhill had earned the nickname “The Beanie Bandit’’ over a series of bank robberies in which he attempted to disguise himself by wearing a beanie over his head.

In a somewhat bizarre coincidence, just a fortnight after being released on bail, Broughill would be found dead. His body was found floating in a Victorian quarry.

He would be the fifth person closely linked to the ringleaders of the gang to be murdered.

Investigations into Broughill’s death by Victorian detectives revealed he had been involved in a series of thefts with the father and son at the centre of Operation Jarrah.

Victorian detectives believe the pair were at the centre of the thefts, with $500,000 worth of property recovered from their property when they were arrested, along with Broughill, on January 13, 1999.

When the trio were released from St Kilda Rd police complex the day after their arrest, Smith Sr claimed they had travelled by public transport to Mildura and were then picked up and taken to Broughill’s Renmark property, about 136km away.

When detectives questioned Smith Sr over Broughill’s murder, he appeared agitated and nervous. He told them he had driven Broughill to Adelaide to enable him to catch a bus to Melbourne. He claims that was the last he saw of him.

Smith Sr had every right to be nervous when being spoken to by Victorian detectives. Just six months later, SA police would charge him and his son with Daly’s murder.

It didn’t come as a surprise to investigating detectives when one of their targets was overheard urging associates to commit another crime.

As part of an Australian Federal Police drug investigation, detectives intercepted the phones of several suspects. Smith Jr was heard urging a criminal associate to bash a man and rob him.

Unfortunately, the associates didn’t bash the target; instead, they stabbed him and he died of his injuries.

They were both convicted over the stabbing death while Smith Jr, then 33, pleaded guilty to assisting an offender and possession of methamphetamine for sale and served a five-year prison term.

While police have so far been unable to take any action against Smith Jr over the murders, his fellow criminals have had more success after he upset a number of them through his drug-dealing activities.

Several years ago, Smith Jr was severely bashed by members of the Finks bikie gang. He suffered severe head injuries and spent several months in rehabilitation at the Hampstead Centre.

He was interviewed by detectives but, not surprisingly, provided no assistance.

Following his rehabilitation, Smith Jr quickly slipped back into his usual lifestyle — trafficking drugs. He has again come unstuck over his criminal activities, this time in the Northern Territory.

In March, he was arrested by NT police in connection with a large-scale cannabis-trafficking racket operating between SA and the NT. Police allege he trucked 500kg of hydroponically grown cannabis from Adelaide to the NT over a three-month period.

Interestingly, his partner in the venture is well-known SA Italian organised crime figure Giuseppe Bruno Romeo — son of notorious Mafia godfather Bruno “The Fox” Romeo. Romeo Jr was arrested in SA and extradited to the NT over the cannabis racket. Both will face the NT Supreme Court shortly.

Meanwhile, Major Crime detectives are continuing investigations into the murders Smith Jr is suspected of committing. While information is occasionally provided about the disappearances and was followed up, nothing of significance had been received for some time.

“We need information, we need people who know what happened to talk to us,’’ Det. Sen. Sgt McEachern said. “Any information on the location of the bodies would also put us in a better position to lay charges.’’

Rewards totalling $1.6 million are available for information on the four SA murders. A reward of up to $1 million is available in Victoria for information on the Broughill murder.

(Produced by Paul Purcell).

Anyone with any information is urged to call Crimestoppers on 1800 333 000.

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