Before the formation of ghettos, which began in the District in December 1939, Jews were encouraged to flee the city. For those who remained the German authorities decided in March 1941 to allocate a then suburban neighborhood, Podgórze District, to become Kraków's ghetto where so many Jews were destined to die of illness or starvation. Initially, most ghettos were open and Jews were allowed to enter and exit freely. However, with time ghettos were generally closed and security became tighter. From autumn 1941, the SS developed the policy of Extermination through labour, which further worsened the already bleak Jewish condition. The ghetto inhabitants were later murdered or sent to German Extermination camps, including Bełżec and Auschwitz, and to Kraków-Płaszów concentration camp. The largest deportations within the District occurred from June to September 1942. More specifically, the Kraków ghetto deportation occurred in the first week of June 1942, and in March 1943 the ghetto was definitely liquidated.