There's an uproar on South African social media after it emerged that the man dubbed "Dr Death", Wouter Basson, has been treating patients years after being convicted of unprofessional conduct by the country's health council.

He was convicted in 2013 for breaching medical ethics when he was involved in the former apartheid government's chemical and biological warfare program.

He was accused of supplying and producing kidnapping drugs, suicide pills and arming mortars with teargas.

The media dubbed him "Dr Death" when details of the secret programme emerged.

Local media report that he has been working as a cardiologist in at least two facilities in the Western Cape province.

His employer, in response to the backlash, said it "cannot prohibit [Health Professions Council of South Africa] (HPCSA) registered doctors, including Dr Basson, from practising unless they are prevented by law from doing so".