Armia Krajowa
In the outskirts of Białystok, among Polish forces concentrated in the Knyszyn Wilderness were: 42nd Home Army Infantry Regiment, and 10th Home Army Uhlan Regiment. The 2nd Home Army Uhlan Regiment operated in the area of Bransk and Hajnówka. This unit destroyed the rail line between Hajnówka and Czeremcha, including a rail bridge, which was blown up. The 76th Home Army Infantry Regiment fought in the area of Ciechanowiec and Lapy