An earthquake that originated 6km underground near the Cango Caves in Western Cape had thousands of people in panic as tremors were felt more than 150km away. The earthquake, which measured 3.5 on the Richter scale, occurred near the towns of Oudtshoorn and Prince Albert yesterday morning.The earthquake is one of several to have occurred in Southern Africa in the past month, with the strongest - which measured five on the Richter scale - occurring near the Mozambican town of Beira.Yesterday's tremors, which lasted several minutes, began as tour groups, including overseas tourists, were about to enter the Cango Caves.Cango Caves spokesman Ntobeko Mangqwengqwe said: "Fortunately no one was injured."He said staff and tourists were immediately taken to safety and the caves shut.Several other tour groups had to be turned away because of the fear of aftershocks."Inspections were conducted by our disaster management team to see if any damage had occurred to the cave formations. None so far has been found."The caves are expected to be reopened today.People in Oudtshoorn said the tremors had caused tables and chairs to move across offices."A lot of people panicked when the quake struck."Gerard Otto, head of the Eden area disaster management centre, which includes the Garden Route area and its surrounds, said the tremors had been felt 150km away from the earthquake's epicentre, with people in George reporting feeling the tremors."No reports of injuries or damage to property were received," he said.Seismologist Ian Saunders of the SA Geoscience Centre said the earthquake was centred in the Prince Albert area."It was a tectonic earthquake, which is a natural release of stress within the earth on a naturally occurring fault line."Earthquakes of this magnitude are extremely common," he said...