At least five people are believed to be trapped after part of the roof of a major state hospital in Johannesburg collapsed, reports say.
The roof caved in at the reception area of the Charlotte Maxeke hospital as construction work was under way to seal a leak, officials say.
Two patients, two construction workers and one hospital staff member have been rescued with minor injuries.
Eyewitnesses said they heard people screaming when the roof collapsed.
Heavy rain was hampering the rescue efforts at the hospital, one of South Africa's biggest.
"At this stage we can neither confirm the number of injuries nor what caused the collapse," a statement from the provincial department of health in Gauteng said.