Large Japanese fleet present off Borneo, Dutch East Indies according to the U.S. Joint Intelligence Committee. Daily summary dated 20 December 1941

An item rereferred to M/A London reporting that the Japanese maintained a probably still increasing fleet off Borneo. The day before were 10 Japanese warships counted, presently 13 and 1 tanker off Miri. A Dutch aircraft scored a hit on a Japanese destroyer.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary No. 10 dated 20 December 1941.