Last September, an unknown gunman shot and killed Brett Kebble, a colourful and well-known white South African mining magnate. The murder - still unsolved by police - took place on a road near Melrose Arch, an upmarket Johannesburg office precinct where the city’s black and white power-brokers mingle. It shocked a business community that prides itself on rectitude and respect for the rule of law. Phumzile Mlambo-Ngcuka, South Africa’s deputy president and a former minerals and energy minister, eulogised Mr Kebble, who was celebrated for his role in deals that increased black ownership of the economy, as a ‘great South African’.

Seven months later, her words are ringing hollow as forensic auditors unravel Mr Kebble’s messy corporate legacy. They have discovered that the slain businessman defrauded two mining houses he headed, Randgold & Exploration and JCI, of nearly R3.5bn (£323m, $577m, €474m), about R1bn of which shareholders will never recover. Auditors are also uncovering evidence of extensive financial ties between the late businessman and prominent members of the ruling African National Congress and its youth league. A list found on Kebble’s desk after his death, headed ‘Loan Account’, included the names of several ANC heavyweights.