The end of the second year of the Korean fighting and the beginning of the third was observed by the Chinese with an attack against the 2d Battalion, 5th Marines, manning JAMESTOWN positions to the left of the regimental sector. Commanded at that time by Lieutenant Colonel Thomas J. Cross, 2/5 was new on line, having relieved 2/1 during the night of 15–16 June. Late in the afternoon of 24 June, the enemy began registering his mortars and artillery on MLR company positions of 2/5 and a portion of the rear area occupied by the battalion 81mm mortars. Chinese incoming, sometimes intense, sometimes sporadic, continued until shortly after 2130. By this time the CCF were moving down their trenches toward a key outpost, Yoke, known also as Hill 159, which was still occupied on daytime basis by the Marines and lay north of the Company F Sector (Captain Harold C. Fuson). Moments later, the 34 men temporarily outposting Yoke saw the Chinese and opened with small arms fire, but the Marine positions were quickly enveloped by the Chinese. The Americans occupying the forward slopes of Yoke suffered many casualties from the intense fires supporting the enemy rush. While the initial attack was in progress, the Chinese were able to position and fire machine guns from behind the outpost and in trenches on the forward slopes. Communist mortars interdicted the Marine supply routes to make normal withdrawal and reinforcement measures difficult. The Marines moved into bunkers, called down pre-planned fires, and continued the defense. Although the Chinese had overrun Yoke, they could not evict the Marines. At about 0300, the enemy withdrew. When the 2/5 troops followed to reoccupy the forward slopes of Yoke, the enemy renewed his attack and struck again. As before, the Marines took to bunkers and called in defensive artillery fires. These boxing fires fell around the outpost perimeter until first light when the attackers withdrew for the second time. Four other outposts in the battalion area were involved in the anniversary attack, but the action around Yoke was by far the heaviest. It resulted in 10 Marines of 2/5 killed and 36 wounded. At Yoke alone, 9 were killed and 23 wounded. Enemy dead were 12 known and 50 estimated killed. Chinese wounded were estimated at 100. At one point during the attack on Yoke, the outpost commander reported that the enemy were wearing gas masks and using tear-gas grenades. Investigation revealed that the Chinese had carried and even worn the masks, but that they had employed white phosphorus grenades rather than tear gas. This was the first instance Marine division personnel had ever encountered of CCF soldiers carrying gas masks in an attack and it was “believed part of the enemy’s hate campaign to impress their troops with the possible use by the UN Forces of CBR (Chemical, Biological and Radiological) warfare.”[138] [138] Selden, _Div Staff Rpt_, p. 16.