Transport of Białystok children

On 21 August 1943, during the liquidation of the Białystok Ghetto, about 1,200 Jewish children were put on trains and taken to Theresienstadt concentration camp, where they were held in isolation from other prisoners. On 5 October, they were told that they would be sent to Switzerland in exchange for German prisoners of war.

Source: Wikipedia — Transport of Białystok children (CC BY-SA 4.0)