Correctional Services said that “matters are under control” at Johannesburg’s Sun City Prison on Wed.
Another South African musician has been shot dead.
Gospel singer Zolile Ndyawe was gunned down in KwaZakhele, Port Elizabeth, on Wednesday night.
His murder comes two weeks after reggae star Lucky Dube was killed in a botched hijacking in Rosettenville, Johannesburg.
Ndyawe was shot in the head and died instantly, after which the robbers took his cellphone.
"The police believe the murderer shot him for his cellphone.
"They also took confidential documents in his possession," said his friend Monde Tshamlambo.
Ndyawe was murdered soon after he finished recording his second album in collaboration with the popular gospel singer, Vuyo Mokoena.
People's poet Mzwakhe Mbuli described Ndyawe as one of South Africa's most-talented singers.
Mbuli raged against what he called the "escalating butchering of musicians".
Ndyawe will be buried in Port Elizabeth next week.