The 26-year-old man was pulled over at a routine check-point in KwaZulu-Natal province, where traffic officials found the children, aged between three and 13, crammed on top of each other for the morning ride to school.
"The man is now behind bars," Colin Govender of the Road Traffic Inspectorate said. The driver is due to appear in court on Thursday.
With the soccer World Cup just months away, police are cracking down on rogue taxi operators in the hope that foreign visitors will use minibuses to get around the country.
Millions of mostly black South Africans use minibus taxis to travel between townships and cities, although many of the vehicles are barely roadworthy and fatal accidents are common.
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