Shortly after dawn on the 4th, the 1st Platoon of engineers went forward and removed the mines ahead of 1/5’s positions. Preparatory fires by 1/11 at 0750 routed a group of enemy on the peak on Baker Company’s front, and the Marine riflemen had a field day as the Reds threw away their weapons and pelted westward. Companies A and B jumped off at 0800 and advanced rapidly over the high ground south of the MSR against negligible resistance. The attackers frequently observed small groups of enemy fleeing in all directions, and many of the Communists were cut down by Brigade air, artillery, and armor. Twelve prisoners were captured before 1/5 reached its half of Brigade Objective One at 1505. This was the high ground south of the MSR at Kang-ni, over 3,000 yards from the line of departure. Shortly after 0800, 3/5 had launched a two-pronged assault against Hill 117, core of the NKPA 9th Division’s resistance the previous day. Company G advanced through Easy Company’s lines just above the MSR and pushed across the intervening rice paddies. The Marines charged over a small knoll in their path but found the enemy positions unoccupied except for several dead. Bohn quickly led the company to the southern slopes of Hill 117, which was strangely quiet by comparison with the tumult of the previous day. In capturing the southern half of the hill, Company G killed only 15 North Koreans. Simultaneously with Bohn’s advance, Company H swung wide to the right and passed through the thin ranks of Dog Company on the northern tip of Hill 117. The attackers drove south against negligible resistance and quickly linked with Company G, securing the objective at 0840. A connecting road runs from Myong-ni to the MSR, tracing the eastern base of Hill 117. Since engineers on the previous night had located the enemy minefield east of the junction on the main road, Taplett moved his headquarters to the MSR via the connecting road. The lead vehicle, a personnel carrier loaded with communications men, struck a Communist mine on the secondary route east of the newly captured objective. The resulting explosion caused 10 casualties. By noon the engineers had cleared the road of several Russian-type mines identical to those found during the night. The two anti-vehicular minefields were among the first such obstacles encountered by the UN forces in the Korean conflict. After seizing Hill 117, Companies G and H continued the attack westward by advancing abreast on the high ground north of the MSR. Contact with 1/5 on the left was maintained, but the 9th Infantry on the right soon fell behind and disappeared from sight.