87 years ago today, on July 31, 1938 (July 5, 1938 in the lunar calendar), an armed conflict broke out between Japan and the Soviet Union in the Zhanggufeng area. On July 31, 1938, an armed conflict broke out between Japanese and Soviet troops near Zhanggufeng on the west side of Hassan Lake. This incident is also known as the Hassan Lake Incident. On July 11, 1938, the Japanese staff headquarters made use of the Soviet army to enter Zhanggufeng, which was at the junction of the borders of China, the Soviet Union and North Korea, to build a position and make a plan to launch a tentative limited war against the Soviet Union. At dawn on the 31st, Lieutenant General Takaguso of the 19th Division commanded the Japanese army to start an attack and occupy Zhanggufeng and Sand Grass Peak. On August 2, the Soviet army, supported by heavy artillery and tanks, launched a counterattack, but failed. On the 6th, the Soviet army concentrated two divisions and launched a second attack. The Japanese suffered heavy casualties. On the 11th, the Japanese and Soviet sides concluded an armistice in Moscow. The Japanese headquarters ordered the 19th Division to withdraw to its original position. But the army still did not accept the lesson and continued to prepare for new military provocations.