In the summer of 1942, German SS and police units deported ~ 265,000 Jews from the Warsaw ghetto to to the Treblinka killing center and ~11,600 to forced-labor camps. More than 10,000 Jews in the ghetto were murdered during these deportation operations. While ~35,000 Jews were granted permission to remain in the ghetto (with another 20,000 remaining in hiding), the eventual deportation of all seemed inevitable.
When German SS and police units resumed mass deportation of the ghetto on January 18, 1943, a group of Jewish fighters, armed with pistols, fought their German guards. Although most of the Jewish fighters died in the battle, the Germans (after deporting ~6000 ghetto residents) suspended further deportations on January 21. Believing they had halted deportations, ghetto residents constructed subterranean bunkers and shelters in preparation for an uprising.
With orders to liquidate the residents, German forces entered the ghetto on April 19, 1943. With most residents in hiding, the streets were deserted. Suddenly, Jewish resistance fighters, armed with pistols, grenades, automatic weapons and rifles, attacked. The Germans, who were forced to retreat outside the ghetto wall, reported 12 men killed or wounded during this first assault on the ghetto.
On the third day of the uprising, the Germans began burning the ghetto, building by building, to force the remaining Jews out of hiding. By May 8, the Germans had effectively razed the ghetto, captured the Jewish command post and and killed the leaders. A few survivors fought on sporadically for several weeks.
Ultimately, the Germans deported almost all of the ~42,000 remaining Jews from the ghetto. With the exception of a few thousand forced laborers, all of these Jews were later murdered.