“Mahomo had been in France and returned home three weeks ago when he was overcome by a sudden illness,” spokesman Sifiso Khanyile said.
“He died on Sunday. A memorial service will be held on Thursday and the funeral will be in Kagiso, near Krugersdorp, on Saturday.”
Mahomo was part of the South African United Front, a movement formed abroad soon after the Sharpeville massacre and the subsequent banning of liberation movements in South Africa.
He travelled extensively on political missions in the 1960s and edited a magazine called Crisis and Change in Britain.
He produced two widely acclaimed films: “Phela-ndaba” (End of Dialogue) and “Last Grave at Dimbaza”. They were shot clandestinely in South Africa and smuggled out of the country in the early 1970s.
“We would like to convey our sincerest condolences to his family, friends and colleagues and hope that his bravery and work will continue to inspire emerging voices in the South African film industry,” Khanyile said.
Mahomo was born in 1930 in the then Orange Free State (now Free State), the son of a Dutch Reformed clergyman. He attended Kroonstad High School in the late 1940s.
Sympathetic to the Africanist group within the African National Congress (ANC), he resigned from the executive committee of the Transvaal Youth League in late 1954 in protest against the expulsion of PK Leballo from the league.
In April 1959 he was elected secretary for culture in the Pan Africanist Congress.