Islands. Kongō was quickly deployed towards the Central Pacific to patrol the sea lines of communication of the German Empire. Kongō returned to the port of Yokosuka, Japan, on 12 September, and one month later, she was assigned to the First Battleship Division. In October, Kongō and her new sister ship sortied off the Chinese coast in support of Japanese army units during the Siege of Tsingtao. Then Kongō returned to Sasebo Naval Base for upgrades to her searchlights. On 3 October 1915, Kongō and Hiei participated in the sinking of the old as a practice target. She was a Russian pre-dreadnought that had been captured in 1905 during the Russo-Japanese War that had next served as an I.J.N. warship. With the defeat of the German East Asia Squadron by the Royal Navy at the Battle of the Falkland Islands in December 1914, there was little or no need for I.J.N. operations in the Pacific Ocean. Kongō spent the rest of World War I either based at Sasebo, or on patrol off the coast of China. In December 1918, following the end of the hostilities of World War I, Kongō was placed in "Second Reserve". In April 1919, she was fitted with a new seawater flooding system for her ammunition magazines. With the conclusion of World War I, and the signing of the Washington Naval Treaty on 6 February 1922, the size of the I.J.N. was significantly limited, with a ratio of 5:5:3 required between the capital ships of the United Kingdom, the United States, and the Japanese Empire, since the latter was responsible for only one ocean, rather than the two of the other countries, and fewer warships for France and Italy. This Treaty also banned the signatories from building any new capital ships until 1931, with no capital ship permitted to exceed in displacement. Provided that new additions did not exceed 3,000 tons of displacement, the existing capital ships were allowed to be upgraded with improved anti-torpedo bulges and armored main decks. By the time that the Washington Naval Treaty had been fully implemented in Japan, only three classes of World War I type capital ships remained active: the s, the Kongō-class battlecruisers, and the s. In April 1923, Kongō gave transportation to Crown Prince Hirohito during his official visit to the Japanese possession of Taiwan. On 14 June 1924, she collided with Submarine No. 62 during maneuvers.