The Allies suffered many defeats in the first half of the war. Two major British warships, and were sunk by a Japanese air attack off Malaya on 10 December 1941. Following the invasion, the government of Thailand formally allied itself with Japan on 21 December. Japan invaded Hong Kong in the Battle of Hong Kong on 8 December, culminating in surrender on 25 December. January saw the invasions of Burma and the Dutch East Indies and the capture of Manila and Kuala Lumpur.