Flooding can be used as scorched earth policy through using water to render land unusable. It can also be used to prevent the movement of enemy combatants. During the Second Sino-Japanese War, dykes on the Yellow and the Yangtze Rivers were breached to halt the advance of Japanese forces. During the Siege of Leiden in 1573, the dykes were breached to halt the advance of Spanish forces. During Operation Chastise during the Second World War, the Eder and Sorpe river dams in Germany were bombed by the Royal Air Force, flooding a large area and halting industrial manufacture used by the Germans in the war effort.