Anatomy of murder: The man who killed his family with an axe

Danielle felt "heartbroken" for Henri when she learned of the axe murders.

It was the most brutal and bloody of killing scenes.

Three family members dead. Another seriously injured in what was clearly a frenzied axe attack. And in the aftermath, the son, the prime suspect, calmly saying he didn't do it.

Perth-born Henri van Breda is now serving three life sentences for the brutal slaughter of his family with an axe in 2015.

Last month a South African court found him guilty of killing his mother, father and brother, and attempting to kill his sister.

Until 2015 the family had led a seemingly charmed life, growing up privileged in Perth, then Australia's Sunshine Coast, before moving back to their South African homeland to yet another luxury home.

And despite the guilty verdicts, there are still people close to the former university student who believe he's innocent, his supporters tell Liz Hayes in an interview to air in Australia on 60 Minutes on Sunday night. They say he's a victim who's been framed.

His girlfriend, Janse van Rensburg, is one of them. His aunt, Leenta Nell, whose sister is dead, is another.

Van Rensburg met van Breda after the axe murders, stood by his side during the trial, and continues to insist he didn't do it.

When they met, she had no idea who he was.

She found out what he was accused of online.

Danielle felt "heartbroken" for Henri when she learned of the axe murders. Photo / Channel 9

"I found out through the internet. I saw an article, and then I saw him. I was like, "Oh. That really does make sense because he does not talk a lot about his family," she tells Hayes.

An incredulous Hayes says: "Your very first reaction was 'Oh. Not Oh my God'?"

"I was very hurt," Van Rensburg says.

"I was actually, not hurt, but I felt really heartbroken for him",

In an interview with South Africa's You magazine in 2016, she said she wanted people to know her boyfriend was not capable of such an atrocity and all he wanted was justice for his family.

"He told me that if I had any questions I can ask him and he'll be honest with me," she said in 2016, when she had been dating him for just four months.

"Anyone who spends a day with him will realise he couldn't do such a thing. I believe in his innocence 100 per cent."

Going inside the bloody crime scene, 60 Minutes reveals why others were far more sceptical of van Breda's protests that he was innocent, and had been spared by another person he insisted was responsible for the axe attack.

"In his version, the same attacker, with the same intent, using the same weapon, but the result is very much different," says Cape Town prosecutor Susan Galloway of Henri's version of events.

Equally sceptical was Detective Sergeant Marlon Appollis, who remains struck by van Breda's calm demeanour when he first saw him after the murders.

"Like total calm. You would expect all the rage and stuff inside, but there was nothing, he was just calm," he says.

The 14-year police veteran says it was one of the most confronting cases of his career, and as police video footage reveals the devastating crime scene, he describes it as "particularly vicious".

As van Breda gave his version of events he remembers thinking "Is it possibly true? Can it be what he's telling me, can it be the truth?"

"To me personally, I say to myself, 'No this can't be'"

But he knew he could not just say to van Breda "you're lying". He had to prove it.

Danielle Janse van Rensburg and Henri van Breda. Photo / Channel 9

Last month, prosecutors did just that, with 23-year-old van Breda given three life sentences for the murders of his parents and brother in South Africa, a 15-year sentence for the attempted murder of his sister and an additional 12 months for obstruction of justice.

The former student of Perth's exclusive Scotch College appeared emotionless as the judge handed the sentences down for the horrific killings at his family's luxury home in Stellenbosch. His lawyers indicated he would appeal the sentence.

Van Breda had denied murdering his brother and parents and leaving his sister Marli struggling with near-fatal injuries to her head, neck and throat after the bloody attack.

The trial generated global interest in how a privileged son unleashed such a brutal attack on his family, whose fortune was estimated at $16 million.

Van Breda had told the court that a late-night intruder had entered the family's luxury residence on the heavily-guarded De Zalze Golf Estate.

Judge Siraj Desai didn't believe him, describing his rampage as "savage and vicious" with "an almost unprecedented degree of disregard for one's family".

"Each murderous attack on a family member is a severe crime and warrants the severest punishment," the judge told the court.

"They were attacks involving a high degree of uncontrolled violence. The victims were unarmed (and) they faced an axe-wielding son or brother, probably not expecting the worst."

"We have heard no explanation … you have shown no remorse.

"I'm searching for some human factor that to some degree diminishes the sheer seriousness of these crimes."