Rescue workers picked through rubble and used sniffer dogs to search for survivors on Wednesday after a soccer pitch-sized section of a mall under construction collapsed near the South African city of Durban, killing one and injuring dozens more.
It was not immediately clear how many people might be still trapped under the rubble after the three-storey shopping mall in the town of Tongaat, 30 km (20 miles) north of Durban collapsed on Wednesday afternoon.
"We have no idea how many are trapped at the moment, but we've only got confirmation of three missing," police spokeswoman Mandy Govender told Reuters.
Sniffer dogs had located one "hot spot" area where workers were now using hydraulic rescue tools to try and break through slabs of concrete and steel bars, emergency services spokesman Chris Botha told broadcaster ENCA.
"It was just total chaos when we first arrived here," he said.
The cause of the collapse was also not clear, although Deputy Mayor Nomvuzo Shabalala said on Wednesday local authorities had tried to halt construction a month ago.
If safety regulations are found to have been flouted, the accident could hurt the ruling African National Congress (ANC) as it moves toward an election next year.
Durban and the surrounding province of KwaZulu-Natal are the home of President Jacob Zuma, and the region has enjoyed a construction boom in the last few years, based in part on government investment in infrastructure improvements.
Besides one confirmed death, 29 people, two of them in critical condition, were rushed to nearby hospitals, which initiated full-scale disaster plans, health officials said.
A high death toll could also sour labour relations in the construction sector, which has an otherwise decent safety record due to the strength of South Africa's unions.
The ANC is expected to win the election expected in April or May next year, although its share of the vote is likely to taper as young post-apartheid South Africans with no knowledge of white-minority rule come of age.