 On the morning of September 1 , 3rd Battalion , 38th Infantry moved in an attack westward from the 23rd Regiment command post near Mosan @-@ ni to open the road to the 1st Battalion . On the second day of the fighting at the pass , the relief force broke through the roadblock with the help of air strikes and artillery and tank fire . The advanced elements of the battalion joined 1st Battalion at 17 : 00 September 2 . That evening , North Koreans strongly attacked the 3rd Battalion , 38th Infantry , on Hill 209 north of the road and opposite 1st Battalion , driving one company from its position . 
