At least 20 South African children were killed Friday when their minibus crashed into a truck and exploded, emergency service said. The accident happened between Verena and Bronkhorstpruit, northeast of South Africa's capital, said a spokesman for ER24. Images shared from the medical service showed a smoking and twisted bus on its side. At least 13 of the children were found dead inside the vehicle, but others were ejected during the crash. The cause of the crash still isn't known but is under investigation.