Three reinforced infantry battalions awaited the advancing Japanese in an arc across Australia's north: Sparrow Force on Timor, Gull Force on Ambon and Lark Force on New Britain. These "bird forces" were overwhelmed: in early 1942, Lark Force was defeated in the Battle of Rabaul (1942) and Gull Force surrendered in the Battle of Ambon and through 1942–3, Sparrow Force engaged in a prolonged guerilla campaign in Battle of Timor. Captured Australian Prisoners of War suffered severe ill-treatment in the Pacific Theatre. Around 160 men of Lark Force were bayonetted after capture at Toll Plantation, while 300 of the surrendering Gull Force were summarily executed in the Laha Massacre and 75% of their comrades perished due to ill-treatment and the conditions of their incarceration. In 1943, 2,815 Australian Pows died constructing Japan's Burma-Thailand Railway In 1944, the Japanese inflicted the Sandakan Death March on 2,000 Australian and British prisoners of war – only 6 survived. This was the single worst war crime perpetrated against Australians in war.