 During the morning of 1 September , Walker weighed the news coming in from his southern front , <unk> in a decision as to which part of the front most needed his Pusan Perimeter reserves . Since midnight the <unk> I Corps had broken his Pusan Perimeter in two places @-@ the <unk> 2nd and 9th Divisions in the US 2nd Division sector , and the <unk> 7th Division and <unk> 6th Division in the US 25th Division sector , below the junction of the <unk> and <unk> Rivers . In the US 2nd Division sector North Korean troops were at the edge of <unk> , the gateway to the corridor leading 12 miles ( 19 km ) eastward to <unk> and the main Pusan @-@ <unk> railroad and highway . 
