As the Japanese approached his position, the German Commander withdrew his forces from the two outer defensive lines and concentrated his troops on the innermost line of defence.
On 17 October 1914 the torpedo boat S-90 slipped out of Tsingtao harbor and, firing a single torpedo, sank the 3,000 ton Japanese cruiser Takachiho with the loss of 271 officers and men. S-90 was unable to run the blockade back to Tsingtao and scuttled itself in Chinese waters when running short on fuel.
It is officially announced that the Navy Department now believes that the Japanese cruiser Takachiho, sunk in Kiao-Chau Harbor on Oct. 17, was torpedoed by the German torpedo boat destroyer S-90. Previous official announcements had it that the cruiser had been sunk by a mine, but German and Chinese reports credited the S-90 with the feat.