South African police have arrested a Thai national accused of organising rhinoceros hunts to sell the animals\' horns on the international black market, officials said Monday. The man, 43-year-old Chumlong Lemtongthai, was arrested at his house in Edenvale, east of Johannesburg at the weekend and is due to appear in court Monday for allegedly organising rhino poaching expeditions masked as legal trophy hunts, said the South African Revenue Service (SARS). The tax authority says Lemtongthai would obtain trophy hunting permits, a limited number of which are issued each year, then buy the rhinos\' horns from the hunters for an average 65,000 rand ($9,600, 6,800 euros) per kilogramme and send them overseas. SARS spokesman Anton Fisher called Lemtongthai a \"leading figure\" in the international rhino horn trade. \"He\'s quite extensively involved at a very high level,\" Fisher told AFP. Booming demand for rhino horn on the Asian black market has been driving a poaching surge in South Africa, home to more than 70 percent of the world\'s remaining rhino population. South African national parks officials say rhino poaching has risen from 13 cases in 2007 to a record 333 last year. And the pace continues to increase -- nearly 200 rhinos were killed in the first half of 2011, according to environmental group WWF. Rhino horn powder is used as a fever-reducer in traditional Chinese medicine. Researchers say the recent surge in poaching is driven by the emergence in Vietnam of a belief that the animals\' horns can cure cancer.