Informant questioned over key witness’s murder

POLICE informant Wiandre Pretorius, who died by suicide at an Astron Energy filling station in Brakpan on Gauteng’s East Rand, was the first person of interest questioned by the police following the brutal murder of Marius van der Merwe.

Van der Merwe, identified during proceedings as “Witness D”, had testified as a key witness before the Madlanga Commission of Inquiry, where he detailed his role — and that of law enforcement officials and private security operatives — in the torture and murder of Emmanuel Mbense.

During his testimony last year, Van der Merwe alleged that Mbense was tortured before being killed, and claimed he was later instructed to dispose of Mbense’s body. His evidence helped Mbense’s family piece together what happened and shed light on aspects of the case that had remained unexplained for more than three years.

Van der Merwe was shot dead outside his home just weeks after testifying at the Madlanga Commission in November 2025, raising concerns about the safety of witnesses linked to the inquiry.

Police national spokesperson Brigadier Athlenda Mathe on Sunday confirmed that Pretorius was taken in for questioning following Van der Merwe’s killing.

After 8am at the Astron Energy filling station in Brakpan, members of the public were walking past the scene where Pretorius took his life, as workers were using brooms and water to clean the area which had been demarcated by red cones.

IOL understands that CCTV footage from the filling station shows the 41-year-old with a 9mm handgun.

“In relation to Wiandre Pretorius, he was a person of interest in murder of Witness D. He was actually the first person of interest that we took in for questioning. We had seized his firearms as well as cellphones that are still in police custody or possession for further investigation. That particular investigation is still ongoing and it is at an advanced stage.

“We won’t comment further on that, save to say that Gauteng detectives are still on the ground, investigating that particular incident. So Wiandre Pretorius was one of two persons of interest right after Witness D was murdered, he was taken into questioning and certain items were seized,” Mathe said.

Mathe added that police are also investigating the alleged hit which Pretorius survived last Thursday, when his vehicle was riddled with bullets.

“Ballistic experts took the necessary evidence and they are examining it. At a later stage we will provide feedback on how far that investigation is,” she said.

The Commission's spokesperson, Jeremy Michaels, confirmed receipt of reports regarding the assassination attempt last week. Michaels stated that Pretorius was not a scheduled witness before the Commission.

“I should clarify that Mr Pretorius was not in the sights of the commission for the moment, and he certainly had not approached the commission with information or requests for assistance with his protection. I am aware that he is the subject of an investigation by another law enforcement agency - I wouldn’t want to get into the detail of that. We are in contact with the relevant law enforcement agencies in that regard," he said.

Earlier, IOL reported that the South African Police Service is investigating whether people linked to Mbense are being systematically targeted and killed.

Mbense, a 51-year-old father of five from Brakpan in Gauteng, was murdered on 15 April 2022. His body was found the following day, dumped in Duduza Dam near Nigel, with his car keys and driver’s licence still in his pocket. His death certificate listed blunt force trauma to the head as the cause of death.

Cape Times