Battle of the Atlantic
- U-39 attacks the a carrier, the HMS Ark Royal, northwest of Ireland but is depth-charged by 3 destroyers and sinks. The crew of 43 is captured.
- The British trawler Hawarden Castle (210t) is lost to gunfire from U-17 in the North Sea.
- The British steamer Vancouver City is sunk by U-28 southwest of Ireland. 3 of the crew are lost.
- U-29 sinks the British steamer British Influence southwest of Ireland. The crew is rescued by the Norwegian steamer Ida Bakke.
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]Poland
German troops enter Gdynia. Guderian's XIX Panzer Corps reaches Brest-Litovsk. The Army of Pomorze launches a surprise offensive around Lowica. Von Rundstedt pulls units from Warsaw and Kielce, but the Polish Gen Tadeusz Kutrzeba keeps all these force occupied for 5 days with hard fighting and tough resistance.[
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