mortars began firing on it. By mid-morning, however, the weather cleared and Allied aircraft soon began arriving at the airfield, disgorging men from the 2/7th who were quickly thrown into the line. That night several counterattacks were fought off and the following day, as a section of guns from the 2/1st Field Regiment arrived, the 17th Brigade went on the offensive. A company of machine guns from the 7th Machine Gun Battalion was also flown in. By 5 February the Japanese began withdrawing from the area. Significant fighting occurred on 9 February, and over the course of the next three weeks further clashes took place as the Australians followed up the retreating Japanese. The last actions came around Buibaining and Waipali and by 26 February the withdrawal was complete with the Japanese establishing themselves around Guadagasal and Mubo. Following this, the 17th Brigade advanced towards Guadagasal, but after supply problems ground this to a halt, throughout March and April a series of patrols were sent out towards Mubo. By late April the brigade was detached to the 3rd Division, a primarily Militia formation, which took up the task of defending Wau. Throughout this time, engineers from the 6th Division, including the 2/1st Field Company, would to improve supply lines throughout the area, cutting a road to Wau. The 2/2nd Field Ambulance also provided support to the brigade's operations, establishing medical services close to the Australian forward areas. Between 22 April and 29 May 1943, the 2/7th Infantry Battalion, at the end of a long and tenuous supply line, unsuccessfully attacked the southern extremity of Japanese lines, the Mubo area, at features known to the Allies as "The Pimple" and "Green Hill", north of Lababia Ridge. In early May, over the course of two days, the 2/7th repelled eight strong Japanese counterattacks, before being relieved. At the same time, the Allies began planning wider operations to capture Lae. As a part of this, Salamaua was also to be taken. Initially, the 3rd Division was to secure Nassau Bay and the 17th Brigade was to capture Mubo and push north towards Mount Tambu to secure Komiatum. Moving over steep, muddy ridges amidst dense, fetid jungle terrain the 2/7th found the going tough and by late May the 2/6th took over the drive towards Nassau Bay. Feeling their way from Lababia Ridge they located a traversable path through the jungle towards the coast