Following reorganization, the division was directly attached to Gen. Stefan Dąb-Biernacki's Northern Front. On 19 September 1939 it took part in the battle of Włodawa against the German 3rd Panzer Division. It then took part in the second battle of Tomaszów Lubelski fighting near Aleksandrów and Tereszpol. Encircled by the 8th Infantry Division from the South, the VII Army Corps from the West and North, and by the advancing Red Army from the East, the division held on to its lines until 26 September 1939, when it finally capitulated.