The first major RAN victory of the war occurred when the cruiser, HMAS "Sydney" sank the German light cruiser, off the Cocos Islands in the Indian Ocean on 9 November 1914. Four Australians were killed in the engagement and another 12 were wounded. Ships of the RAN helped provide naval cover for the ambitious landings at Gallipoli, and the submarine "AE2" broke the blockade of the Dardanelles to harass Turkish shipping but was later sunk and her crew captured in the Sea of Marmara.