seven small Japanese freighters and luggers which were found anchored at Lingkas, sinking or damaging all but one of them. On 30 April, the 2/4th Commando Squadron and the 57th Battery of the 2/7th Field Regiment were landed on the nearby Sadau Island in order to support the engineers tasked with clearing the obstacles off the invasion beaches. This force rapidly secured the undefended island. The landing on Sadau Island was the first time Australian soldiers had landed on non-Australian territory in the Pacific since late 1941 (Australian participation in the New Guinea Campaign from 1942 onwards was limited to the Australian portion of New Guinea). The only Allied losses in this operation were aboard , which was damaged when she struck a mine while supporting the landing. The task of clearing the beach obstacles at Lingkas was assigned to the 2/13th Field Company. These defences comprised rows of barbed wire, wooden posts and steel rails which extended 125 yards from the beach. At 11:00 on 30 April, eight parties of engineers went forward in LVTs and landing craft to clear the obstacles. The engineers were supported by the guns on Sadau Island and Allied warships and aircraft. Operating under Japanese fire the engineers cleared all the obstacles obstructing the landing beaches. While heavy casualties had been expected, the 2/13th completed their task without loss. Battle Landing The main invasion force arrived by sea off Tarakan in the early hours of 1 May. Supported by a heavy air and naval bombardment, the 2/23rd Battalion and the 2/48th Battalion made an amphibious landing at about 08:00. The 2/23rd Battalion disembarked from American LVTs into deep mud at "Green Beach" on the southern flank of the beachhead, and overcame several small Japanese positions in the hills around Lingkas. At nightfall it dug in along the main road to Tarakan Town (which had been designated the "Glenelg Highway" by the Australian planners). The 2/48th Battalion had a much easier landing at "Red Beach" on the northern end of the beachhead with most troops disembarking from their LVTs near dry land. The battalion pushed north along the "Anzac Highway" and nearby hills, and rapidly secured a number of pillboxes behind the beach as well as the oil storage tanks. By the end of the day the 2/48th held positions in the hills to the west of Tarakan Town. The 2/24th Battalion also began landing