JOHANNESBURG - Gauteng police believe they're making steady progress in the murder investigation of Madlanga Commission witness Marius van der Merwe.
The security boss was shot dead outside his home in Brakpan over a week ago.
Van der Merwe testified at the Madlanga Commission in November, claiming that he'd been asked to dump the body of a suspect three years ago.
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Hours before he was shot dead by AK-47-wielding gunmen, he had planned to blow the whistle on what he called “state” involvement in illegal mining.
Though police have remained tight-lipped on the motive for the killing, it’s understood they are looking at and investigating various motives.
A vehicle, apparently used by the gunmen, was found abandoned in Alex three days after Van der Merwe was shot dead.
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eNCA understands the vehicle had been spotted by Alex community members on the same day of the murder.
When questioned by police, sources say the owner claimed he'd rented out the vehicle.
Another suspect who'd allegedly rented the car from the owner claimed that he'd been hijacked.
A second vehicle believed to have been used by Van der Merwe's killers has still not been found.
eNCA understands that detectives have also made inroads into the attempted murder of Van der Merwe in September.
Men in a white Mahindra bakkie opened fire on him while he was patrolling at a site on Main Reef Road used by zama zamas.
Afriforum, representing the family of Emmanuel Mbense, has received feedback from police watchdog IPID on the 2022 Brakpan murder case.
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But they're not satisfied with the progress three years later.
IPID told eNCA that their investigation in relation to the Brakpan murder case is at its final stage.
Meanwhile, Van der Merwe's loved ones will be holding a memorial service for the slain whistle-blower on Wednesday afternoon.