Japanese activities in the Dutch East Indies increasing according to the U.S. Joint Intelligence Committee. Daily summary dated 19 February 1942

An item reported that American bombers believed to have sunk one large and one small Japanese transport off Banka Island, Dutch East Indies. Japanese aircraft attacked Surabaya, Dutch East Indies although just causing light damage and loosing 5 bombers. Also Koepang, Dutch was attacked by Japanese aircraft and the J.I.C. believed that an early landing on Timor was a real possibility.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. MR0423. U.S. Joint Intelligence Committee. Daily summary No. 71 dated 19 February 1942