Blaichman heard that a group of Jews were hiding in the forest, so after two days with the farmer, he made his way to the forest and found more than one hundred Jews living in an encampment of small bunkers in the forest. He realized that the group was in constant danger. Blaichman encouraged the group to form a defense unit to guard the camp even though they had no firearms. In December 1942 the group managed to acquire firearms from a local Polish farmer. (However, according to another biography, it was only in summer of 1943 that Blaichman left the Głos family and joined the resistance). In late January Blaichman and some of his fellow Jewish partisans received shelter from Polish farmer Bolesław Dąbrowski; however the Germans raided their shelter and many Jews were killed, alongside with Dąbrowski who was executed by Germans shortly afterward. Five decades later, in 1994, the Yad Vashem Institute posthumously awarded Bolesław Dąbrowski the title of Righteous Among the Nations. Over time, Blaichman's unit increased in size. They were joined by refugees from Markuszow and expanded to sixty fighters. In the spring of 1943, Blaichman encountered Samuel Gruber. Gruber's group consisted of men who had fought in the Polish Army and knew how to use explosives and mines. The two groups joined together and became a more effective fighting force. By September 1943, the communist People's Army realized that the Blaichman and Gruber groups could be a dependable ally in the fight against the Germans and provided them with supplies that had been parachuted in by the Soviet air force. Now equipped with hand grenades, explosives, land mines, machine guns, and ammunition, the group could be even more successful in fighting the Germans. In 1944, Blaichman's group received an order from the People's Army to move east and join forces with another Jewish partisan unit in the Parczew area commanded by Yechiel Grynszpan. Gruber was appointed deputy commander and Blaichman, at the age of 21, became the unit's youngest platoon commander. In July 1944, the Soviet Red Army advanced from the east and entered the Parczew forest. Also that month, Lublin was taken from the Germans by the Soviets, and Blaichman's partisan group entered the city. Near the end of the war and immediately afterward (April to 19 July 1945) he has worked for the Polish communist secret police (Office of Public Security), as the temporary head of the Department of Prisons and Camps ("Wydział Więzień i Obozów") in the Kielce's Voivode Office of Public Security ("Wojewódzki Urząd Bezpieczeństwa Państwowego", WUBP).