On the night of July 24, 1942, the ghetto of Dereczyn was liquidated; between 3,000 and 4,000 Jews were murdered and placed in a mass grave.
Before the Germans swept Dereczyn, some 250 Jews evaded execution and fled into the forests. They were assisted by another survivor, 33-year old Dr. Yehezkel Atlas who had fled from Kozlowszczyzna, in the Slonim district of western Belarus, where he saw his sister and parents murdered. He was the physician of a partisan group commanded by Pavel Bulak and Boris Bulat, and he brought the refugees from Dereczyn to the two Soviet commanders. There was already a partisan fighting group of Soviet and Polish soldiers, but Atlas announced his intention to form an all-Jewish unit, to give the survivors of Dereczyn vengeance for their murdered families.
Bulak dismissed him, insisting Jews were not fighters, and in any case they did not have weapons to prove themselves. Furthermore, Bulak did not want Atlas, although he was a skilled tactician, to be a partisan leader; he was essential as a physician. Dr. Atlas was adamant and convinced Bulak enough that the commander sent the Jewish men to prove their merit on a dangerous operation — half-expecting failure. When Atlas and the others returned with newly attained arms, Bulak allocated forces for an all-Jewish partisan unit.
One Jewish partisan who came from Dereczyn, Gertrude Boyarski, described her choice to join the fighting unit under Bulak instead of the family camp:
On August 10, 1942, Dr. Yehezkel Atlas received permission to attack the Germans at Dereczyn. Under the authority of Bulak and Bulat, Atlas led 300 partisans in an armed attack on the German garrisons. They successful took control of the town, capturing 44 German policemen and killing almost 20 in the struggle. After raiding the supplies, the Jewish partisans now all had high Russian boots, leather knapsacks, shirts, and a number of small, good-quality arms and ammunition. Atlas ordered the 44 captured German policemen atop the mass grave outside Dereczyn, where they were lined up and executed.
After the operation, Atlas told his unit: