sentences:  The city had been under constant attack by the Luftwaffe since the early morning of 1 September.Initially the only organized units available to him were four infantry battalions, anti-aircraft artillery and anti-aircraft machine guns detachments under colonel Kazimierz Baran, composed mostly of fire-fighter brigades and volunteers supervised by colonel Tadeusz Bogdanowicz and Julian Kulski, the deputy president of Warsaw.The AA artillery had 86 pieces of anti-aircraft artillery, as well as an unknown number of anti-aircraft machine guns.