held back for medical experiments. The Czechoslovak government-in-exile initiated diplomatic manoeuvers to save the remaining Czech Jews after its representative in Bern received the Vrba-Wetzler report, written by two escaped prisoners, Rudolf Vrba and Alfred Wetzler, which warned that the remaining family-camp inmates would be gassed soon. The BBC also became aware of the report; its German service broadcast news of the family-camp murders during its women's programme on 16 June 1944, warning: "All those responsible for such massacres from top downwards will be called to account." The Red Cross visited Theresienstadt in June 1944 and were persuaded by the SS that no one was being deported from there. The following month, about 2,000 women from the family camp were selected to be moved to other camps and 80 boys were moved to the men's camp; the remaining 7,000 were gassed between 10 and 12 July. Selection and extermination process Gas chambers The first gassings at Auschwitz took place in early September 1941, when around 850 inmates—Soviet prisoners of war and sick Polish inmates—were killed with Zyklon B in the basement of block 11 in Auschwitz I. The building proved unsuitable, so gassings were conducted instead in crematorium I, also in Auschwitz I, which operated until December 1942. There, more than 700 victims could be killed at once. Tens of thousands were killed in crematorium I. To keep the victims calm, they were told they were to undergo disinfection and de-lousing; they were ordered to undress outside, then were locked in the building and gassed. After its decommissioning as a gas chamber, the building was converted to a storage facility and later served as an SS air raid shelter. The gas chamber and crematorium were reconstructed after the war. Dwork and van Pelt write that a chimney was recreated; four openings in the roof were installed to show where the Zyklon B had entered; and two of the three furnaces were rebuilt with the original components. In early 1942, mass exterminations were moved to two provisional gas chambers (the "red house" and "white house", known as bunkers 1 and 2) in Auschwitz II, while the larger crematoria (II, III, IV, and V) were under construction. Bunker 2 was temporarily reactivated from May to November 1944, when large numbers of Hungarian Jews were gassed. In summer 1944 the combined capacity of the crematoria and outdoor incineration pits was 20,000 bodies per