 In September 1960, the leaders split, with President Kasa-Vubu declaring prime minister Lumumba deposed from his functions, and vice versa.The stalemate was ended with the government's arrest of Lumumba.In January 1961, he was flown to the rich mining province of Katanga, which by that time had declared a secession from Léopoldville under the leadership of Moïse Tshombe (with active Belgian support).