 Of the 26 field artillery pieces that the Japanese possessed in the region, 18 were captured by the Australians during the campaign, while 28 out of their 36 heavy machine-guns were also lost.At the start of the campaign, the Australian Army had been the only ground force engaging in combat with the Japanese in the region.By the end, though, the involvement of US forces in the region had increased as the US Army took over responsibility for the main Allied effort from the Australians.