A bus has veered off a road and plunged down an embankment on a steep mountain pass in northern South Africa, killing at least 42 people and leaving another 49 passengers injured.

The crash happened on Sunday night on a highway near the town of Louis Trichardt, about 400km north of the capital, Pretoria.

The transport ministry said the victims included seven children, 17 men and 18 women.

Six people were critically injured and another 31 had serious injuries and had been taken to several hospitals.

One critically injured child was airlifted to a hospital, the ministry said.

Images released by authorities showed the blue bus lying upside down in the embankment with rescuers working underneath it to search for victims.

The Limpopo provincial government said rescue operations continued

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