On August 12, 1945.

One of the main targets of the March 9-10, 1945 firebombing raid was to destroy the Japanese Army’s atomic bomb development infrastructure. The Navy had a competing program in Korea that went unscathed. On August 12 there were several reports of bright white light in Korea, but the Americans did not use a 3rd bomb yet which was targeted to hit Tokyo. As the Soviets advanced all evidence was destroyed except some small paper fragments detailing the Navy program. Russia got everything else