The withdrawal of RCT-1 (-) and attached units from Koto-ri commenced on the afternoon of the 10th. The 3d Battalion, it will be recalled, had relieved RCT-7 units the day before on Objectives A, B and C, and the 1st Battalion occupied Objective E. The regimental plan called for 1/1 to hold the Hill 1081 area and protect the MSR until the other units of the regiment passed through, whereupon Schmuck’s battalion was to pull out with the tanks at the end of the column as the rear guard. The movement from the Koto-ri perimeter commenced at 1500 when H&S Company of RCT-1 departed. The 2d Battalion (-) of the 11th Marines fell in behind, followed in order by a detachment of the 185th (C) Engineers, USA, the 2d Battalion of the 31st Infantry, USA, the 2d Battalion of RCT-1, the Division Reconnaissance Company and Lieutenant Colonel Milne’s tank column, consisting of Companies B and D of the 1st Tank Battalion, the Tank Company of the 31st Infantry, USA, and the Tank Platoon of the 5th Marines AT Company.[611] [611] 1stMar _SAR_, 26; 2/1 _SAR_, 19; 1stMar _(S-3) URpt 13_, 16–17. The Marine Provisional Tank Platoon had reached Koto-ri with only two M4A3 tanks, one of which had to be cannibalized. Then the platoon was disbanded and integrated with its remaining M4A3 into B and D Companies. All the other tanks in the column were M-26s. As the last elements left Koto-ri the 92d FA Battalion at Chinhung-ni began laying heavy concentrations on the evacuated base. Only scattered shots were received by the tail of the column from Chinese troops mingling with the Korean refugees. Several small enemy groups on the flanks of the column were taken under fire and dispersed.[612] But with 3/1 guarding Objectives A, B and C, no serious opposition developed during the first stage of the withdrawal. [612] CO 1stMar msg to CG 1stMarDiv, 1700 10 Dec 50; Col C. A. Youngdale Comments, 19 Nov 56. _Completion of Division Breakout_ At dusk on 10 December all indications made it appear that the movement of the 1st Marine Division southward would be completed according to plan with only minor losses of personnel and equipment. Following the seizure of Hill 1081, casualties had been comparatively light and enemy resistance ineffectual. Then, between midnight and 0100 on 11 December, two reverses occurred in areas the Marines supposed to be safe. The MSR south of Chinhung-ni was under the protection of troops of the 3d Infantry Division--Task Force Dog at Chinhung-ni, and two battalions of the 65th Infantry in the vicinity of Sudong and Majon-dong. It was manifestly impossible, of course, for the Army troops to guard every yard of the road, for the rugged terrain offered many potential ambush sites.[613] Guerrilla activity had been reported near Sudong, but the division trains and the 5th and 7th Marines had passed through without incident.