While waiting for an opportunity to launch this operation , the Alsos Mission learned that uranium ore that had been taken from Belgium in 1944 had been shipped to the '' Wirtschaftliche Forschungsgesellschaft '' ( WiFO ) plant in Stassfurt , which was captured by the 83rd Infantry Division on 15 April . As it was in the occupation zone allocated to the Soviet Union at the Yalta Conference , the Alsos Mission , led by Boris Pash and accompanied by Lansdale , arrived on 17 April to remove anything of interest . Over the following ten days , 260 truckloads of uranium ore , sodium uranate and ferro-uranium weighing about 1,000 tons were taken away
Yalta Conference
Yalta Conference
John Lansdale Jr.