German troops captured Belgrade in the Serbia region of Yugoslavia as Hugarian troops also crossed the border into Yugoslavia, joining the invasion. On the Danube River in Yugoslavia, German Ju 87 Stuka dive bombers, sinking river monitor Drava (54 were killed, 13 survived) while forcing three others, Morava, Sava, and Vardar, to be scuttled. To the south in Greece, German SS troops overran British and Australian troops south of Vevi, forcing the Allies to fall back from the Aliakmon Line to the Mount Olympus Line to block the German troops at Vevi from advancing further. On the same day, British anti-aircraft cruiser HMS Coventry, destroyer HMS Decoy, destroyer HMS Encounter, and troopship Glenroy evacuated a battalion of troops, 1,000 tons of supplies, and 40 vehicles from the Greek island of Lesbos in the Aegean Sea near Salonika
