The following is the order of battle of the Riverine Flotilla of the Polish Navy, an integral part of the Polish Navy in the period between the world wars. Staff and the headquarters Initially subordinate to the Referee of the Riverine Fleet in the Ministry of Military Affairs in Warsaw, in 1932 it was separated as a semi-independent branch of the navy based in Pińsk. In 1939 the commander of the Riverine Flotilla was Cmdr. Witold Zajączkowski and his chief of staff was Cmdr. Władysław Szczekowski. Other members of the staff were: Deputy commanding officer Cmdr. Henryk Eibel Artillery officer Cmdr. Włodzimierz Kleszczyński Technical officer Cmdr. Wacław Trzebiński Signals officer Cmdr. Bronisław Witkowski Intelligence officer Cmdr. Narcyz Małuszyński Head surgeon Cmdr. Władysław Kozłowski Chaplain Maj. rev. Henryk Antonowicz Flags officer Cmdr. Janusz Marciniewski Riverine Flotilla Staff vessels ORP Admirał Sierpinek command vessel (armed paddle steamer) S 1 liaison motorboat S 2 liaison motorboat Nr. 5 speed-boat Combat groups 1st Combat Group ORP Kraków river monitor (Capt. Jerzy Wojciechowski) ORP Wilno river monitor (Capt. Edmund Jodkowski) ORP Zuchwała gunboat ORP Zaradna gunboat KU 16 (KU being an acronym of Kuter Uzbrojony, that is armed cutter in Polish; similar in shape and armament to later PT boats and PBRs) KU 17 armed cutter KU 18 armed cutter KU 19 armed cutter KU 21 armed cutter K 20 barrack ship (krypa in Polish terminology) ORP Generał Sikorski anti-air defence armed paddle steamer (Capt. Władysław Fidosz - name uncertain) Nr. 1 speed-boat 2nd Combat Group ORP Warszawa river monitor (Capt. Jan May) ORP Horodyszcze river monitor (Capt. Andrzej Marzecki) KU 22 armed cutter KU 24 armed cutter KU 25 armed cutter KU 26 armed cutter K 8 barrack ship ORP Hetman Chodkiewicz anti-air defence armed paddle steamer (Capt. Edward Kulesza) Nr. 2 speed-boat 3rd Combat Group ORP Pińsk river monitor (Capt. Jan Kierkus) ORP Toruń river monitor (Capt. Bolesław Parydzaj) KU 7 armed cutter (reconnaissance) KU 23 armed cutter (service) KU 27 armed cutter KU 28 armed cutter KU 29 armed cutter K 10 barrack ship ORP Generał Szeptycki minelayer (armed paddle steamer) Nr. 3 speed-boat Support units Mine and gas warfare detachment ORP Mątwa minelayer, capable of gas warfare and supporting a troop of engineers T 1, T 2 and T 3 T 5 class river minesweepers T 4, T 5, T 6 and T 7 T 1 class river minesweepers Liaison unit