Here is the info I found from ***en.wikipedia.org/wiki/Soviet_invasion_of_Manchuria
1. Soviet invasion of Muchuria began on August 9, 1945. Japan surrendered on August 15, 1945.
2. Kwantung Army continued fighting after August 15, 1945 because of communication problems.
3. 83,737 Japanese soldiers were killed and 640,276 Japanese soldiers were captured. the Soviet invasion and the defeat of Japan's military forces were regarded as Japan's worst land defeat in its military history.