One of the men who robbed and murdered Shirley van Rensburg and then dismembered her body before burying it in a warthog burrow was declared a dangerous psychopath 17 years ago.

Correctional Services authorities were warned against his release on parole after a Grahamstown High Court judge ruled that Wayne Nass, 34, needed therapy while in custody. The judge made the comments as he sent Nass to jail for 20 years for murder and robbery on February 14 1992.

He was released on parole in December 2004.

On Friday, the Johannesburg High Court found Nass and his co-accused Boyce Matya, 48, guilty of the murder of Van Rensburg eight months after Nass had been paroled - on August 20 2005.

Acting Judge Majake Mabesele accepted Matya's confession made before a magistrate. Matya admitted to helping Nass attack Van Rensburg in her Northriding cottage and then loading her body into the boot of her own car.

Matya drove Van Rensburg's white Mazda, with her body in the boot, to Nkwe Game Lodge in Thabazimbi, where they were working.

He told the magistrate that the next day the two of them discovered an animal hole, into which they shoved Van Rensburg's body. They covered the warthog burrow with stones and branches.

The court also accepted that Matya made a similar confession to investigating officer Superintendent Peet Marais before he took police officers to the spot where they buried Van Rensburg, and to another hole where they hid her driving licence and other documents.

In September 2005 Matya was found in possession of Van Rensburg's vehicle in King William's Town in the Eastern Cape. He led the police to Nass, who was hiding at his sister Dalene Nel's home at Gonubie in East London.

In his evidence, Nass tried to distance himself from the murder. He admitted to assisting Matya hide the stolen vehicle, but Judge Mabesele would have none of it.

The judge also accepted the account of awaiting-trial prisoner Christopher Bester, who testified that Nass had confessed his role in the murder a year later.

Judge Mabesele said Bester did not know Van Rensburg before her death, and his version of the murder was corroborated by Matya's confession.

Nass was also linked to the murder when police found Van Rensburg's DNA on his blood-stained boots. The court also accepted Nel's evidence that Stephanie Crause, 32 - Nass's girlfriend - wanted Nel to help her to dispose of Van Rensburg's frying pan and takkies while the two were hiding in her house.

Crause was charged for being an accessory after the fact of murder and defeating the ends of justice, but was acquitted.

The guilty verdict allowed Van Rensburg's sister, Lorna Moss, to smile for the first time since her agonising death.

Sentence will be passed on September 25.