At least one person was killed and up to 50 more were trapped under rubble yesterday after a half-built shopping mall collapsed near the South African coastal city of Durban, emergency services and police said.

A further 26 people had been taken to hospital in the town of Tongaat, 30 km (20 miles) north of Durban, Chris Botha, a spokesman for the Netcare 911 emergency service, told Reuters.

It was not yet clear what had caused the collapse of the three-storey building, which had been under construction for some time, residents told Reuters.

If safety regulations are found to have been breached, the accident could sour already fraught labour relations in South Africa’s construction sector and might have ramifications for the ruling African National Congress as it moves towards an election next year.

Television footage showed police and rescue workers walking over large piles of rubble and twisted metal lying next to a railway track. Large parts of the building had completely given way.

“The scene is extremely horrific ... concrete big blocks have fallen on to people,” Botha told broadcaster ENCA from the scene. “The guys are busy using hydraulic rescue equipment to break through the concrete and get to some of the patients.”

Ambulances ferried the injured to nearby hospitals, which initiated full-scale disaster plans.

“There are no really severe injuries,” said Jenny Meer, manager of the Mediclinic Victoria hospital in Tongaat that had admitted eight patients.

“It’s mainly broken bones, soft tissue injuries and a bit of shock. But obviously there are a lot of patients that are still trapped on site,” she said.

Emergency services spokesman Botha said others were more seriously injured.

Durban and the surrounding province of KwaZulu-Natal is the home of President Jacob Zuma. The region has enjoyed a massive construction boom in the last few years, based in part on huge government investment in infrastructure improvements.

Zuma and the ruling African National Congress (ANC)face a general election in April or May next year.