Jewish partisans were fighters in irregular military groups participating in the Jewish resistance movement against Nazi Germany and its collaborators during World War II. A number of Jewish partisan groups operated across Nazi-occupied Europe, some made up of a few escapees from the Jewish ghettos or concentration camps, while others, such as Bielski partisans, numbered in the hundreds and included women and children. They were most numerous in Eastern Europe, but groups also existed in occupied France and Belgium, where they worked with the local resistance. Many individual Jewish fighters took part in the other partisan movements in other occupied countries. In total, the Jewish partisans numbered between 20,000 and 30,000. The partisans engaged in guerrilla warfare and sabotage against the Nazi occupation, instigated teens and freed prisoners. In Lithuania alone, they killed approximately 3,000 German soldiers. They sometimes had contacts within the ghettos, camps, Judenrats, and with other resistance groups, with whom they shared military intelligence. In Eastern Europe, many Jews joined the ranks of the Soviet partisans: throughout the war, they faced antisemitism and discrimination from the Soviets and some Jewish partisans were killed, but over time, many of the Jewish partisan groups were absorbed into the command structure of the much larger Soviet partisan movement. Soviet partisans arrived in the western Ukraine in 1943, and consisted of Russians, Ukrainians, Poles, and Jews, and were smaller in size than units in Belarus, which was more suitable for partisan warfare. Released Soviet archive data suggest that Jews accounted for 5.2% of the partisans in Ukraine. Jewish partisans had to overcome great odds in acquiring weapons, food, and shelter and in evading capture. They typically lived in dugouts (known in Russian as zemlyankas, землянка) in forest camps. Nazi reprisals were brutal, employing collective punishment against their supporters and the ghettos from which the partisans had escaped, and often using "anti-partisan operations" as pretexts for the extermination of Jews.