By August, the KPA had pushed back the ROK Army and the Eighth United States Army to the vicinity of Pusan in <answer>southeast Korea</answer>. In their southward advance, the KPA purged the Republic of Korea's intelligentsia by killing civil servants and intellectuals. On 20 August, General MacArthur warned North Korean leader Kim Il-sung that he was responsible for the KPA's atrocities. By September, the UN Command controlled the Pusan perimeter, enclosing about 10% of Korea, in a line partially defined by the Nakdong River.
Where did the Eighth United States and ROK get pushed back to?
southeast Korea