As Operation Thursday began to turn sour, Wingate's replacement as commander of Special Force requested 23 Brigade, but instead the brigade marched into Burma on 3 April 1944 to defend the routes into Assam and cover the northern flank of Fourteenth Army in its counter-offensive towards Kohima. As the brigade advanced, it found elements of the Japanese 124th Regiment covering the flank of the 31st Division. These flank guards, aided by storms, dense jungle, and precipitous mountains, imposed considerable delays on 23 Brigade's advance towards Jessami. After the Relief of Kohima the British continued towards Imphal, still with 23 Brigade as flank guard on the Kharasom–Ukhrul axis, with the task of cutting Japanese communications back to the Chindwin River.