Konwicki continued his studies underground and joined the eighth Oszmiana Brigade of the Home Army that took part in the nationwide guerrilla operation code-named Operation Tempest and Operation Ostra Brama. He later disarmed and went into hiding from the Soviet Army. In November 1944, he joined Tur's (Witold Turonek) unit and fought until April 28, 1945 - one of the last guerrilla units in the area. After the war Wilno (retrieving its name as Vilnius in the process) was annexed by the Soviet Union and Konwicki was expatriated.