"We have experienced five fatalities already, that includes a police diver," Oscar Mabuyane, the Eastern Cape provincial premier told reporters Sunday while visiting affected areas.

Sudden rains pounded parts of the southern province including East London, on the Indian Ocean coast, on Saturday.

Within hours, low lying areas were severely flooded, a local government official told AFP.

Among the worst hit was Mdantsane, a sprawling township on the outskirts of East London.