The company which owns the prospecting rights to the abandoned mine in which at least 30 "illegal miners" were trapped says heavy rain may have been a trigger for the shaft's collapse.
Chinese-owned bullion producer Gold One owns the prospecting rights to the abandoned gold shaft, however was not currently working in it.
"The illegal miners have dug a tunnel right next to it to access the shaft and it has collapsed behind them," Gold One spokesman Grant Stuart said.
Emergency services in South Africa have been using a crane to shift a large concrete slab obstructing the shaft.
More top news
School fees, pricey private medical care and the fear of interest rate rises mean even those on £200,000 are feeling the pinch.
Overnight it will be cooler and fresher but most places will stay dry with a nippy start to Sunday.
X Factor contestant Raign seems to impress the Wembley audience with her own song even though Cheryl finds her "really annoying".