Chris Hani's murderer, Clive Derby-Lewis, was attacked in Pretoria Central Prison on Wednesday, the department of correctional services has confirmed.
Derby-Lewis is currently serving a prison sentence of 25 years for his role in the murder of the South African Communist Party general secretary, Chris Hani, in 1993.
The Mail & Guardian understands that Derby-Lewis and his co-conspirator in the Hani murder, Janusz Walu??, were stabbed several times by an inmate on Wednesday. They were then struck on the head with locks.
The department of correctional service's spokesperson Manelisi Wolela said the two have been treated for the wounds in prison, and the attacker was locked in a cell.
Derby-Lewis was denied medical parole in 2011, and again in 2013. The 77-year-old is reportedly suffering from cancer and gangrene.
Derby-Lewis, a former Conservative Party politician, loaned Walu?? the gun he used to assassinate Hani on April 10 1993. Hani was shot four times and died outside his Johannesburg home, amid sensitive negotiations between the ANC and the National Party.
Walu??, a Polish immigrant with right-wing links, was arrested within 15 minutes of shooting Hani.
Fears of retaliation from the ANC or a race war rang throughout the country, prompting Nelson Mandela to address the nation on live television and deliver his famous speech in which he called for calm.
"This killing must stop. We are a nation in mourning … yet we must not permit ourselves to be provoked by those who seek to deny the freedoms that Chris Hani gave his life for," said Mandela.
Violence erupted across the country in the days that followed, in which at least 70 people were killed.
Derby-Lewis and Walu??? were sentenced to death but were later remitted to life sentences.