interior carried out their operations separately from the conventional forces that focused mainly upon the coastal areas. However, some co-ordinated action was achieved during the campaign. During July, guerrillas assigned to Operation Semut captured Marudi, on the Barem River, as part of efforts to disrupt the Japanese withdrawal from Miri. A strong Japanese counter-attack retook the village from the lightly armed Semut operatives, after which the guerrillas linked up with conventional Australian infantry from the 2/17th Battalion to capture it once again on 15 July. During the course of their involvement in the campaign, the 20th Brigade's casualties were relatively light, suffering only 40 casualties. Throughout late June and into August, RAAF aircraft including Mosquitos and Beafighters attacked Japanese targets throughout North Borneo, including barges, shipping, barracks and airfields, sinking an 800-ton vessel near the Tabuan River and destroying several Japanese aircraft on the ground. Wirraways were also used to provide tactical reconnaissance, and other fighters flew close air support sorties. Weston Another landing was made by Allied forces on 16 June on the mainland at Weston, in the north-eastern part of Brunei Bay. The 2/32nd Battalion, which had previously been held back as the divisional reserve, forced its way ashore near Padas Bay. After taking Weston, patrols were sent out to Beaufort, which was inland. Due to the lack of roads and the indefensible nature of the railway track that led to the town, it was decided to advance along the Klias River, while a secondary force moved along the Padas River. As a part of this phase of the operation, minor landings were made at Mempakul on 19 June and at Sabang on 23 June by elements of the 2/43rd Battalion and the 2/11th Commando Squadron. Kibidang was captured the same day by the 2/43rd, while the 2/32nd advanced further along the Padas River and the two battalions married up. Following this, reinforcements in the form of two companies from the 2/28th Battalion were transferred from Labuan to take over rear area security while plans were made for the main attack on Beaufort. The Allies assessed that Beaufort, which lay on the main Japanese avenue of withdrawal, was held by between 800 and 1,000 Japanese troops seeking to keep key egress routes open. On 27 June, the Australians attacked the town. The 2/43rd Battalion was assigned the task of the main assault, while the 2/32nd Battalion was tasked