One of three sons, Patrick came to live in South Africa when as a teenager he followed his migrant worker father to work in the mines of South Africa performing odd jobs. After his father's death, Chamusso's mother remarried and bore another daughter. He worked in various jobs on the mines and later found work as a house painter and street photographer.
When he was 28, he got a job at the Sasol's synthetic fuel plant at Secunda (Secunda CTL), the largest coal liquefaction plant in the world, located several hours east of Johannesburg. Although not formally educated, he advanced quickly and ended up as a driver, a position that was well-paid. His main job was to fetch coal from a neighboring mine and bring it into the refinery. A talented soccer player who had formerly played for local leagues, his abilities later made him popular among his co-workers and in the community.
Chamusso was arrested in 1980 by South African Special Branch for conspiring with the ANC to bomb the Secunda refinery, a crime he insisted he did not commit. He was later released without charges being laid. He reported that he had been tortured whilst a prisoner. He fled to Mozambique where he joined Umkhonto we Sizwe, the militant arm of the ANC.
After military training, he returned to South Africa where he single-handedly carried out a second, partly successful, bombing at Secunda, which - as was intended - resulted in no casualties. After a massive manhunt, he was arrested and ultimately sentenced to 24 years in prison on Robben Island. In 1994, as the apartheid system began to be dismantled, having served 10 years Chamusso was released under the new government's amnesty policy.