On the night of 8 February 1904, the Japanese naval fleet under Admiral Heihachiro Togo opened the war with a surprise attack by torpedo boat destroyers on the Russian ships at Port Arthur, badly damaging two Russian battleships. The attacks developed into the Battle of Port Arthur the next morning. A series of indecisive naval engagements followed, in which the Japanese were unable to attack the Russian fleet successfully under shore batteries ("coastal guns") of the harbor and the Russians declined to leave the harbor for the open seas, especially after the death of Admiral Stepan Osipovich Makarov on 13 April 1904.