Police say the motive for yesterday's shooting which killed Lawrence Moepi, a forensic services director at an auditing firm, is still unknown.
Police are still searching for four men in connection with the murder of a forensic services director shot dead at his auditing firm's offices in Houghton, Johannesburg, Gauteng police said on Saturday.
"No one has been arrested yet," Lt-Col Lungelo Dlamini said around 9am.
Asked to comment on media speculation that Lawrence Moepi could have been killed in a hit on Friday, Dlamini said: "We haven't established a motive yet".
It was believed that Moepi was followed to his workplace, SizweNtsalubaGobodo, by men in a Volkwagen Golf.
He was shot dead as he got out of his car. Nothing was stolen.
According to a statement on the firm's website, Moepi had worked closely with the police's commercial crime unit and the now defunct Directorate of Special Operations, known as the Scorpions.
In his capacity as PricewaterhouseCoopers forensic services director, Moepi testified in the fraud trial of former Scorpions official Geoffrey Ledwaba.
It was reported that he had been appointed to work on the probe into the country's multi-billion rand arms deal.–Sapa.