The 83-year-old was reportedly shot after two robbers forced their way into his house.

His wife was assaulted during the incident.

“When Netcare911 paramedics arrived on scene, we found that the elderly man had already died before our arrival due to the gunshot wound he sustained,” a statement from the Netcare911 ambulance and rescue service said.

“Netcare911 paramedics declared the man dead on scene before handing over the body to the Boschkop police.

“The man’s wife was assaulted but after she was assessed by our paramedics, we found that she did not require any medical care.

“The exact detail to the cause of the incident will remain a subject for police investigation and comment.”

Hettema had competed for South Africa at the Melbourne 1956 Olympic Games, representing the country in the individual and team road race events.

He also narrowly missed out on a medal in the men’s 4,000 metres team pursuit alongside Abe Jonker, Bobby Fowler and Jimmy Swift.

The quartet were beaten in the bronze medal ride by Britain’s Don Burgess, Mike Gambrill, John Geddes and Tom Simpson.

Simpson later went on to claim world road race gold medal in 1965 before dying at the Tour de France two years later when ascending Mont Ventoux.

As well as cycling, Hettema made an impact as a rally driver as he won five South African Championship titles, including three consecutive titles from 1967 to 1969.