The shooting took place on the night of September 22 in the KwaMakhutha township, about 30 kilometres (19 miles) south of Durban on the country’s east coast.
According to police, the attackers entered the house where a party was in progress and unleashed a barrage of gunfire, leaving at least 11 dead, including a woman believed to be pregnant.
Three additional partygoers were injured but survived the attack.
Police released a statement confirming the death toll and the presence of a pregnant victim, and said they are actively searching for the three suspects believed to be responsible.
Authorities have not yet disclosed a motive for the attack, and no arrests have been reported as of the latest update on September 23.