The black-and-white photo illustrates the brutality of the apartheid regime: young Hector Pieterson carried by a fellow schoolboy after being gunned down by police on June 16 1976 in Soweto.
Thirty years on, photographer Sam Nzima remembers the day that was to change the destiny of South Africa, and end his career as a photojournalist.
"They were all happy. They were carrying placards, not guns," recounted Nzima, now 71, who lives in the village of Lillydale near the Kruger National Park in north-east South Africa.
Assigned by his newspaper The World to cover the protests, Nzima showed up early in the morning and was in the middle of the students when police opened fire.
"The shooting was just at random," he said.
Hector Pieterson was struck down by a bullet to the head. A friend picked him up to take him to the hospital.
Nzima snapped six shots from behind the 50mm lense of his Pentax SL. The third shot turned out to be the best.
It showed the lifeless body of Pieterson carried by Mbuyisa Makhubu, his face torn by pain. Pieterson's sister Antoinette dressed in her school uniform can be seen running alongside.
After taking the pictures, Nzima removed the film from his camera and hid it in his sock. A few hours later, it was splashed on the front page of The World and the next day in British newspapers. The world had discovered the bloody repression of the student uprising. And Nzima discovered police harassment and fear.
Accused of portraying South Africa in a bad light, he was hunted down by police and forced to leave Soweto where he lived with his wife and four children.
He moved to his hometown of Lillydale and opened a bottle store. His photograph was soon after censured and The World shut down, but Nzima was still the target of police harassment.
He was advised against pursuing any subversive activities in the village.
Over time, the police stopped paying attention to Nzima but he never again picked up his camera.
"There were no newspapers here. Take pictures for what ?" he said.
The picture has brought Nzima some fame -- he has met former United States president Bill Clinton and Nelson Mandela -- but little money.
At the end of a long battle, he recovered the rights to the photograph in 1998 but it has been difficult to enforce them.
He is proud of his work and bitter about the lack of recognition from the government.
Nzima has kept his Pentax SL and may one day sell it off in an auction to raise funds for a museum that he hopes to open behind his house. - AFP