More than 400 people have been displaced after a tornado swept through Ekurhuleni, east of Johannesburg, damaging a mall, hospital and numerous households. According to the City of Ekurhuleni, the thunderstorm blew roofs off about 200 households in Winnie Mandela leaving an estimated 400 people displaced. Other areas damaged by the storm include 100 shacks and 20 houses in Hospital view.The tornado also ripped the roof off Phumulani Mall and damaged Tembisa Tertiary Hospital. The Gauteng department of health said the hospital fence, carports, about 20 vehicles, three ambulances and the roof of one building had been destroyed and trees were uprooted. Watch: Second tornado wreaks havoc in GautengA tornado wreaked havoc in the east of Johannesburg near OR Tambo International airport on Tuesday afternoon - the second to hit Gauteng within the last 24-hours.  Ekurhuleni Emergency Services spokesman William Ntladi said three people suffered minor injuries and were treated at the scene. ER24's Werner Vermaak said debris and twisted metal scattered across the mall might have caused the injuries. A search and rescue operations at the mall found no one trapped in the debris. Video courtesy Jana van den Heever via FacebookEkurhuleni has established a Joint Operational Centre (JoC) to assist victims of the tornado,  providing salvage sheets as an interim measure to cover the roofs, distributing food parcels and blankets as well as deploying social workers and mobile clinics. Rabasotho and Olifansfontein community halls have been provided to accommodate victims. Victims of the thunderstorm in Ekurhuleni can contact the JoC on 011-458-0911.   According to the South African Weather Service, tornadoes are not as uncommon as you might think. They can occur basically anywhere where a thunderstorm is possible, with most observed in Gauteng, the Free State and KwaZulu-Natal. Some 65% of the South African tornadoes are classified as F0 or F1 (light damage), while more than 90% are classified as F0, F1 or F2 (considerable damage) or less. Meteorologists rely on weather radar to provide information on developing storms. Currently in the USA, scientists can only predict a tornado 20-minutes before it touches down.Pictures, videos: Snow, rain and tornadoes - extreme weather plays havoc on SAFrom snow to flooding and tornadoes, extreme weather conditions have been playing havoc across the country this week. In KwaZulu-Natal heavy rains caused at least four deaths and the death toll is expected to rise as violent weather wreaks havoc.Three people were electrocuted by electricity cables during the torrential rain in Durban, and in Chatsworth, a mother-of-two drowned when her car was washed off a flooded bridge.Disaster and emergency teams worked through the night to evacuate residents of flooded homes and to clear roads that were potential dangers for road users...