Recently the struggle stalwart had been vocal about state capture, saying thieves were masquerading as revolutionaries while they stole from the country.
Johannesburg mayor Jolidee Matongo said Montsitsi died on Thursday.
He described Montsitsi as “one of the strongest but very humble leaders” he has ever known.
“Bra Dan will forever be remembered as one of the astute young leaders of 1976 who led the youth revolution during the tough times of apartheid. It was his humbleness that saw him easily succeed in persuading other young people to join the fight against the apartheid system,” said Matongo.
“He gave of himself selflessly to the liberation struggle and made sure to impart his knowledge to the youth who came after him. Losing Bra Dan is a great loss for the people of Johannesburg, especially those of us who were looking forward to learning more from his leadership wisdom.”
TimesLIVE