A multi-storey building under construction in South Africa's coastal city of George collapsed on Monday trapping about 48 workers in the rubble, the city hall said.
Seventy people were on the site at the time of the collapse, of which 22 have been taken to hospital, a city spokeswoman said.
Mario Ferreira, spokesperson for the charity Gift of the Givers, assisting at the site, told AFP that rescue workers had "communication with some of the people under the rubble".
It was still unclear what caused the building, with an underground parking lot, to fall in the early afternoon.
Photographs shared by the municipality showed a flattened construction site with multiple rescue services present.
"There have been people taken out, seriously injured. At this stage we haven't got any fatalities yet," said Ferreira.
Resue operations continued into the evening at the site.
