They destroyed all transportation in and out of Leningrad in August and September 1941.
Army Group North retreated from Leningrad in 1944 after one of the deadliest sieges in history. Indeed, rather than occupying it, this prong of the German Army had orders to completely annihilate the city. They destroyed all transportation in and out of Leningrad in August and September 1941. Thereafter, the city experienced heavy bombardment by artillery and the Luftwaffe for two and a half years. Leningraders starved, mostly surviving on less than half a gram of sawdust-laden bread a day. Reports of cannibalism were also common. By the time the Red Army finally beat back the Germans in January 1944, between 600,000 to a million people had died.