The South African Weather Service has warned of further severe thunderstorms over Gauteng on Thursday afternoon. The warning comes flash floods caused choas in Johannesburg and Ekurhuleni. The Gauteng government has confirmed that the death toll following the flash floods has risen to four. A number of vehicles were trapped on the N3 around the Gillooly's interchange. The provincial government says it's doing everything possible to clear the affected roads. It has activated the Johannesburg Disaster Management Centre to co-ordinate government efforts to investigate the extent of damage. Forecaster, Wayne Venter.