The Australian 7th and 9th Divisions converged on Lae, which fell on 16 September. MacArthur advanced his timetable, and ordered the 7th to capture Kaiapit and Dumpu, while the 9th mounted an amphibious assault on Finschhafen. Here, the offensive bogged down, partly because MacArthur had based his decision to assault Finschhafen on Willoughby's assessment that there were only 350 Japanese defenders at Finschhafen, when in fact there were nearly 5,000. A furious battle ensued.