the evening. Eventually the increasing Japanese numbers, poor siting of defensive positions, and lack of effective communications, allowed Japanese forces to exploit gaps in the Australian lines. By midnight the two 8th Division infantry brigades, the 22nd and 27th, were separated and isolated, and the 22nd had begun withdrawing towards Tengah. By 1:00 am, further Japanese troops – bringing the total to 13,000 – had begun landing and as the main Australian force was pushed back towards Tengah airfield, small groups of troops that had been bypassed by the Japanese fought to rejoin their units as they had withdrawn toward Tengah airfield. Around dawn on 9 February a further 10,000 Japanese troops landed, and as it became clear that the 22nd Brigade was being overrun and it was decided to form a secondary defensive line to the east of Tengah airfield and north of Jurong. The 27th Brigade had not yet faced an attack. However, the next day, the Japanese Imperial Guard made a botched landing in the northwest, suffering severe casualties from drowning and burning oil in the water, as well as Australian mortars and machine guns. In spite of the 27th Brigade's success, as a result of a misunderstanding between Brigadier Duncan Maxwell and Bennett, they began to withdraw from Kranji in the north. That same day, communication problems and misunderstandings, led to the withdrawal of two Indian brigades, and loss of the crucial Kranji–Jurong ridge through the western side of the island. The Australian battalions attempted several local counterattacks as they attempted to shore up their lines. One such attack, saw the Bren carriers of the 2/18th Battalion conduct a mobile ambush. Nevertheless, the British Commonwealth forces steadily lost more ground, with Japanese penetrating to within five miles of Singapore urban centre, by 10 February capturing Bukit Timah. On 11 February, knowing that his own supplies were running low, Yamashita called on Percival to "give up this meaningless and desperate resistance". The next day the Allied lines attempted to stabilise along the Krangi–Jurong line on west side of the island, with an ad hoc battalion of Australian reinforcements being committed to hasty counterattack. This was eventually cancelled, but the battalion was not recalled, and it was later set upon by the Japanese 18th Division as the Japanese recommenced offensive actions. Meanwhile, the 27th Brigade attempted to retake Bukit Timah, but the attack was repulsed by stubborn defence