The so-called Manchurian Massacre took place in 1931 when the Japanese army sought and pronounced an excuse to attack Manchuria, so the Chinese army, knowing that, did not respond to the attack, and this event is known as the Invasion of Manchuria. What was really a massacre was the Nanking Massacre, when Japanese soldiers from Shanghai launched into Nanking and easily defeated the Chinese army, and then massacred some 300,000 people, committed robbery. The official position of the People's Republic of China was first that this number of 300,000 included both killed soldiers and victims of the massacre, but later this claim was changed, that it was about 300,000 people massacred exclusively killed soldiers.
The answer is: Nanking Massacre.