In accordance with Corps OpnO 7, the rear boundary of the 1st Marine Division had been moved north to a line just south of Hagaru. The 3d Infantry Division had the responsibility for the area south of Hagaru, but this unit had so many other commitments that it could assign few troops to the task. General Smith was granted permission, therefore, to retain garrisons at Koto-ri and Chinhung-ni. This left the 3d Infantry Division responsible for the protection of the MSR from Sudong southward to Hamhung.[357] [357] Smith, _Notes_, 727–729. Corps OpnO 7, in short, provided for a wide envelopment to be spearheaded by the 1st Marine Division on 27 November. The other arm of the pincers, of course, was to be the Eighth Army; but on the evening of the 25th came the disturbing news that its right wing, the II ROK Corps, had been hurled back by a surprise CCF counterstroke. This reverse took place in the vicinity of Tokchon, about 70 air miles southwest of Yudam-ni.[358] [358] _Ibid._, 728; EUSAK _WD_, 26 Nov 50. EUSAK intelligence reports, as it proved, were not far off the mark in estimating enemy strength on the Eighth Army front at 149,741 troops at this time.[359] During the past few days, however, estimates of probable enemy courses of action had been so reassuring as to justify the confidence of CinCFE’s communique on D-day. Even the setback of the 25th was not regarded as alarming. [359] It is interesting to note that this is an increase of 95,741 over EUSAK’s estimate of the day before. EUSAK _PIR 136_, encl. 2, 3, in EUSAK _WD_, 25 Nov 50. “With the possible exception of the relatively vague situation on the east flank,” said the next day’s G-2 report, “the enemy reaction to the EUSAK attack has been one of active defense with local counterattacks in strength.” The enemy’s probable course of action was believed to be “an active defense in depth along present lines employing strong local counterattacks in conjunction with continued guerrilla activities with bypassed units; limited air activity; and further reinforcement by CCF or USSR forces.”[360] [360] EUSAK _PIR 137_, 4, and encl 4, 3, in EUSAK _WD_, 26 Nov 50. On the X Corps front the reorientation of the attack to the west gave General Smith a long-sought opportunity to collect his dispersed units and achieve a relative degree of concentration. The release of RCT-1 from its Huksu-ri mission made it possible to bring that infantry regiment up behind the other two. This move in turn enabled RCT-5 to advance east of the Chosin Reservoir and RCT-7 to push on to Yudam-ni.