The supporting platoon from Company E joined in organizing the defense of the recaptured outpost, which came under a deadly torrent of accurate fire that forced the Marines to seek the protection of the reverse slope, nearer the MLR, where they held out until midafternoon before falling back.

He and his staff planned a sudden thrust at Bunker Hill, possession of which would enable his command to dominate Siberia and observe movement beyond the PVA outpost line.

[1]: 496 The Bunker Hill assault force, Company B, 1st Battalion, 1st Marines under the operational control of Batterton's 2nd Battalion—reached the crest by 22:30 and began driving the PVA from the slope nearest the MLR.

In the wake of the assault force, other Marines and members of the Korean Service Corps manhandled sandbags, wire, and shovels up the hill to help Company B organize the defenses of the objective against the counterattack that was certain to come.

The volume and accuracy of the shelling increased at about 15:00, a barrage that lasted an hour and forced the Marines to seek the protection from direct fire afforded by the reverse slope.

[1]: 496–7 While the battle raged on Bunker Hill, 1st Marine Division commander General John T. Selden moved his reserves closer to the fighting.

As daylight faded into dusk on 12 August, the Marines defending the reverse slope of Bunker Hill struggled to improve their hurriedly prepared fortifications, for the anticipated PVA night counterattack.

The comparatively gentle incline of the reverse slope of the ridge that culminated in Bunker Hill reduced the amount of dead space that could not be covered by grazing fire from the Marine position.

[1]: 497–8 Just as the Marines had attacked Siberia on the evening of 11 August to divert attention from Bunker Hill, the PVA sought to conceal the timing of their inevitable counterthrust.

Mortars and artillery shelled Combat Outpost 2, overlooking the Panmunjom corridor on the left of the sector held by the 3/1 Marines, and also harassed the MLR nearby.

[1]: 498–500 The 1st Marines responded to the fighting of 13 and 14 August by reinforcing both Bunker Hill and the nearest segment of the Jamestown Line, the so-called Siberia Sector, in anticipation of further PVA attacks.

As part of the preparation, Company H, 7th Marines, which still held Bunker Hill, patrolled the slopes where the PVA had launched several attacks but found no Chinese, a situation that rapidly changed.

The bombardment by mortars and artillery attained a volume of 100 rounds per minute before ending at about 04:00, when the PVA apparently realized they could not overwhelm Bunker Hill and called off the attack.

Because the battalion manned the outposts only in daylight, the PVA simply occupied Elmer, farthest to the southwest, after dusk on 6 August and employed artillery fire to seal off the approaches and prevent the Marines from returning after daybreak.

During an unsuccessful attempt to regain the third of the outposts, Private First Class Robert E. Simanek saved the lives of other Marines by diving onto a PVA hand grenade, absorbing the explosion with his body, suffering severe though not fatal wounds, and earning the Medal of Honor.

On the night of 4 September, PVA gunners began shelling the outpost and probing its right flank, but small arms fire forced the enemy to pull back.

Apparently confident that the barrage had neutralized the defenses, the attackers ignored cover and concealment and moved boldly into an unexpected hail of fire that drove them back.

The attackers tried to correct their mistake only to come under fire from their fellow PVA who had penetrated the extreme right of Bunker Hill's defenses and may have mistaken their comrades for counterattacking Marines.

The 2nd and 3rd Battalions, 5th Marines fought to defend their outpost line from Allen in the west, through Bruce, Clarence, Donald, Felix, and Gary, to Jill in the east against a succession of attacks that began in the early hours of 5 September.

Private First Class Alford L. McLaughlin killed or wounded an estimated 200 PVA, victims of the machine guns, carbines and grenades that he used at various times during the fight, and survived to receive the Medal of Honor.

Private First Class Fernando L. Garcia, also earned the award, although already wounded, he threw himself on a PVA grenade, sacrificing his life to save his platoon sergeant.

Hospitalman Third Class Edward C. Benfold saw two wounded Marines in a shell hole on Outpost Bruce; as he prepared to attend to them, a pair of grenades thrown by two onrushing PVA soldiers fell inside the crater.

When dawn broke on 5 September, Company I still clung to Outpost Bruce, even though only two bunkers, both on the slope nearest the Jamestown Line, survived destruction by mortar and artillery shells.

On the morning of 6 September, the defenders of Outpost Bruce beat off another attack, finally calling for box-me-in fires that temporarily put an end to infantry assaults.

The PVA struck first at Hill 124, attacking by flare-light from four directions but failing to dislodge the squad dug in there, even though most of the Marines suffered at least minor wounds.

Moreover, anything salvaged from Bunker Hill had to travel over a primitive road described as "particularly tortuous", which made the transfer "of first the ammunition and then the fortification materials a physical ordeal.