During process of reorganization of the Nowogrodek Area of the Home Army, the UBK units created a battalion, which became part of the 77th Infantry Regiment of the Home Army, under Boleslaw Piasecki. In February 1944 the battalion had around 700 soldiers (some sources put the number at around 500). The unit took part in the Operation Tempest, fighting the Germans around Lida and Wilno (see: Wilno Uprising), where it suffered heavy losses.