Officials in South Africa have launched an investigation after the deaths of seven jobseekers who collapsed in the heat while undergoing a fitness test for positions as traffic officers.

The chief transport official for KwaZulu-Natal province, Willies Mchunu, has suspended further tests.

The state-owned South African Broadcasting Corporation reported that several tens of thousands of people took the fitness test late last week, even though only 90 jobs were available.

They were required to run 2.5 miles in temperatures of more than 30C, and many collapsed from dehydration and heat exhaustion. Some received hospital treatment.

South Africa's official statistics show that the unemployment rate is 25%, an indication why so many were applying for the 90 jobs.