Ten crew members were rescued after their fishing vessel sunk off the west of the Western Cape near Saldahna Bay.
According to the South African Maritime Safety Authority Coordinating Centre (SAMSA) in Cape Town, the sinking of the fishing trawler, registered as Ankoveld/ZR4388, occurred early on Saturday morning.
Samsa said in a statement that the vessel's skipper who was among the 10 rescued crew confirmed that the Ankoveld experienced difficulties after it had begun to take water in the engine room. It then capsized and sank.
"After being alerted to the incident, the MRCC through the rescue sub-rescue centre in Saldanha mobilised a vessel nearest the incident, the Atlantic Leader, which successfully rescued the sunken fishing vessel's 10 member crew that had already abandoned ship to life rafts," read the statement.
A navigational warning had been promulgated warning other vessels sailing in the vicinity of the sunken vessel.
SAMSA officials in Saldanha Bay arrived at the scene to conduct an investigation into the incident.
All 10 crew members were safely taken to Laaiplek harbour.
Clean-up operations underway at Durban harbour following ship fire
This is the second incident this week involving a fishing trawler.
On Friday, six people died when a fire broke out on board a vessel docked at the Durban harbour.
A statement issued by TNPA said that the vessel was docked at the jetty for its bi-annual maintenance repairs when the incident happened.
The repair work was being carried out by a private Mozambican ship repair contractor at the repair quay owned by TNPA.
Samsa said that the bodies of the crew were transported to a mortuary in Durban.
Five of the deceased were Mozambican nationals while a sixth crew member was of Portuguese origin.