 At 09 : 35 September 2 , while the North Koreans were attempting to destroy the engineer troops at the southern edge of <unk> and clear the road to <unk> , Walker spoke by telephone with Major General Doyle O. <unk> , Deputy Chief of Staff , Far East Command in Tokyo . He described the situation around the Perimeter and said the most serious threat was along the boundary between the US 2nd and US 25th Infantry Divisions . He described the location of his reserve forces and his plans for using them . He said he had started the 1st Provisional Marine Brigade toward <unk> but had not yet released them for commitment there and he wanted to be sure that General of the Army Douglas MacArthur approved his use of them , since he knew that this would interfere with other plans of the Far East Command . Walker said he did not think he could restore the 2nd Division lines without using them . <unk> replied that MacArthur had the day before approved the use of the US Marines if and when Walker considered it necessary . A few hours after this conversation Walker , at 13 : 15 , attached the 1st Provisional Marine Brigade to the US 2nd Division and ordered a co @-@ ordinated attack by all available elements of the division and the marines , with the mission of destroying the North Koreans east of the <unk> River in the 2nd Division sector and of restoring the river line . The marines were to be released from 2nd Division control as soon as this mission was accomplished . 
