Discussions included the question of Jewish refugees who had been liberated by Allied forces and those who still remained within German-occupied Europe. The uprising January revolt On 18 January 1943, the Germans began their second deportation of the Jews, which led to the first instance of armed insurgency within the ghetto. While Jewish families hid in their so-called "bunkers", fighters of the ŻZW, joined by elements of the ŻOB, resisted, engaging the Germans in direct clashes. Though the ŻZW and ŻOB suffered heavy losses (including some of their leaders), the Germans also took casualties, and the deportation was halted within a few days. Only 5,000 Jews were removed, instead of the 8,000 planned by Globocnik. Hundreds of people in the Warsaw Ghetto were ready to fight, adults and children, sparsely armed with handguns, gasoline bottles, and a few other weapons that had been smuggled into the ghetto by resistance fighters. Most of the Jewish fighters did not view their actions as an effective measure by which to save themselves, but rather as a battle for the honour of the Jewish people, and a protest against the world's silence. Preparations Two resistance organizations, the ŻZW and ŻOB, took control of the ghetto. They built dozens of fighting posts and executed a number of Nazi collaborators, including Jewish Ghetto Police officers, members of the fake (German-sponsored and controlled) resistance organization Żagiew, as well as Gestapo and Abwehr agents (including the alleged agent and Judenrat associate Dr Alfred Nossig, executed on 22 February 1943). The ŻOB established a prison to hold and execute traitors and collaborators. Józef Szeryński, former head of the Jewish Ghetto Police, committed suicide. Main revolt On 19 April 1943, on the eve of Passover, the police and SS auxiliary forces entered the ghetto. They were planning to complete the deportation action within three days, but were ambushed by Jewish insurgents firing and tossing Molotov cocktails and hand grenades from alleyways, sewers, and windows. The Germans suffered 59 casualties and their advance bogged down. Two of their combat vehicles (an armed conversion of a French-made Lorraine 37L light armored vehicle and an armored car) were set on fire by the insurgents' petrol bombs. Following von Sammern-Frankenegg's failure to contain the revolt, he lost his post as the SS and police commander of Warsaw. He was replaced by SS-Brigadeführer Jürgen Stroop, who rejected von Sammern-Frankenegg's proposal to call in bomber aircraft