Plans for the northward advance brought up the vital problem of providing security for the 78-mile main supply route (MSR) and the parallel railway stretching along the coast from Wonsan to Hamhung. Division orders of the 28th assigned RCT-5 (less 2/5), temporarily under the operational control of RCT-1, the responsibility for the security of the Munchon and Yonghung areas, 16 and 57 miles north of Wonsan respectively. Company A, 1st Tank Battalion, attached to RCT-5, had orders to establish blocking positions on three main roads joining the MSR from the west.[200] [200] 1stMarDiv _OpnO 18-50_, 28 Oct 50; Smith, _Notes_, 463–464. RCT-7, after being partially issued cold weather clothing at Wonsan, moved by road and rail to the Hamhung area during the last three days of October. The 1st Motor Transport Battalion and Division Reconnaissance Company were attached along with other reinforcing units, since this regiment had been designated to lead the advance of the 1st Marine Division to the Manchurian border.[201] [201] 7thMar _SAR_, 12; CO 7thMar tel to G-3 1stMarDiv, n.t., 28 Oct 50; 7thMar msg to CG 1stMarDiv, 0850 1 Nov 50; 1stMarDiv _OpnO 18-50_, 28 Oct 50. See the detailed account of the move in Col R. G. Davis Comments, 7 May 56. RCT-7 did not receive all of its cold weather clothing until after it reached Koto-ri. MajGen H. L. Litzenberg Comments, 18 Jul 56; LtCol M. E. Roach Comments, 17 May 56; LtCol W. D. Sawyer Comments, 7 Sep 56. RCT-5 completed a motor march meanwhile from its assembly area near Wonsan to assigned positions along the Wonsan-Hamhung MSR. General Almond’s OI-15 (30 October) had directed the dispatch of two Marine RCTs to the Hamhung area, which meant that Lieutenant Colonel Murray’s regiment was to follow RCT-7. On the 31st General Smith ordered him to advance a battalion to Chigyong, eight miles southwest of Hamhung. Murray selected his 1st Battalion and directed that one of its companies be detached to relieve an RCT-7 company guarding the Advance Supply Point at Yonpo Airfield, five miles southwest of Hungnam.[202] [202] CG 1stMarDiv msg to CO 5thMar, 2118 31 Oct 50; CO 5thMar msg to CO 1/5, 1013 1 Nov 50; Smith, _Notes_, 463–464; 5thMar _SAR_, 8–9; 5thMar _URpt 2_; 1/5 _SAR_, 5; 3/5 _SAR_, 5; Col A. L. Bowser Comments, 23 Apr 56. Two additional Marine units were assigned to assembly areas along the MSR. The 1st Tank Battalion (less Company C, attached to the 1st Marines) moved up to Munchon and regained its Company A. Since the landing of the 11th Marines (less the battalions attached to RCTs) the artillery regiment (-) had occupied positions at Munpyong-ni, five miles northwest of Wonsan.[203] [203] 1stMarDiv msg to 1stTkBn, 1750 31 Oct 50; 1stTkBn _SAR_, 11. The move was made 1 Nov. 11thMar _URpt 2–28 Oct 50_.