Coinciding with this heavy fighting at the Pusan Perimeter in the south a new and disturbing element appeared far to the north. In Tokyo and Washington, American military leaders studied reports they received indicating that Chinese Communist troops were moving north through China and concentrating along the Yalu River opposite Korea.
An incident at this time added to the build-up of threatening storm clouds to the north. On 4 September, a twin-engine bomber wearing a red star passed over a screening ship of a U.N. naval task force operating in the Yellow Sea off the west coast of Korea, approximately at the 38th Parallel. The bomber continued on toward the center of the naval formation and opened fire on a U.N. fighter plane patrol which returned its fire and shot it down. A destroyer of the task force recovered the body of one of the bomber crew members-he was an officer of the Armed Forces of the Soviet Union. [24-75]