rate sinking as much as 70%. Those assets of UMHK not seized by Mobutu were absorbed by the Société Générale de Belgique, later becoming part of Union Minière (now Umicore). Göran Björkdahl (a Swedish aid worker) wrote in 2011 that he believed that the death of the-then United Nations Secretary-General Dag Hammarskjöld was a murder committed in part to benefit mining companies like Union Minière, after Hammarsköld had made the UN intervene in Congo's Katanga crisis after a call for intervention by prime minister Lumumba. Björkdahl based his assertion on interviews with witnesses of the plane crash near the border of the DRC with Zambia, and on archival documents. References External links List of directors of UMHK – scroll down to Union Minière du Haut Katanga (de facto rulers) Scramble for Katanga (downloadable book) Umicore UMHK records, TANKS archive, University of Manchester Library Belgian Congo Congo Free State Copper mining companies of Belgium Mining companies of the Democratic Republic of the Congo Defunct mining companies Mining in Katanga Province Société Générale de Belgique Belgian colonisation in Africa Copper mining companies of the Democratic Republic of the Congo Uranium mining companies of Belgium Uranium mining in the Democratic Republic of the Congo History of the Democratic Republic of the Congo Manhattan Project Non-renewable resource companies established in 1906 Non-renewable resource companies disestablished in 1966 Companies disestablished in 1966 1966 disestablishments in Belgium 1906 establishments in the Congo Free State 1966 disestablishments in the Democratic Republic of the Congo Belgian companies established in 1906 Trading companies of Belgium Trading companies established in the 20th century Trading companies disestablished in the 20th century