The siege of Leningrad (; ) was a prolonged military blockade undertaken from the south by the Army Group North of Nazi Germany against the Soviet city of Leningrad (now Saint Petersburg) on the Eastern Front in World War II. The Finnish army invaded from the north, co-operating with the Germans until Finland had recaptured territory lost in the recent Winter War, but refused to make further approaches to the city. Also co-operating with the Germans since 1942 in August: the Spanish Blue Division that was transferred to the southeastern flank of the siege of Leningrad, just south of the Neva near Pushkin, Kolpino and its main intervention was in Krasny Bor in the Izhora River area.