 Meanwhile , <unk> 's 2nd Battalion , under Major <unk> Tamura , assembled for their planned assault against Hill 80 from the jungle south of the ridge . Marine observers spotted Tamura 's preparations and called in artillery fire . At about 22 : 00 , a barrage from twelve 105 mm ( 4 @.@ 1 in ) guns hit Tamura 's position . In response , two companies of Tamura 's troops — numbering about 320 men — charged up Hill 80 with fixed bayonets behind their own barrage of mortar fire and grenades . Tamura 's attack hit Company B of the Marine Parachute battalion and also <unk> Company B , pushing the <unk> off the east side of the ridge into a draw below the <unk> . To protect the exposed <unk> Company B , <unk> immediately ordered them to pull back onto Hill 123 . 
