Eighty-six years ago today, on May 9, 1939 (March 20, 1939), the Eighth Route Army dealt a heavy blow to the Japanese army in the Wutai Mountain area. Brigade commander Wang Zhen (right 1) was captured on the interrogation day of the upper and lower slender waist. On May 9, 1939, the Japanese 1st 09th Division and the independent mixed 3rd Brigade each had a total of about 5,000 people. They were dispatched from Wutai, Daying and other places in Shanxi Province to "sweep" the northeastern area of Wutai Mountain in multiple ways, attempting to jointly attack the organs of the Jin Chaji Military Region and the main force of the Eighth Route Army in the Wutai Mountain area. The Jin Chaji Military Region was responsible for restraining the Japanese army that invaded eastward from Wutai Mountain with one force, and concentrated the main force of the 38th Route Army's 1st 120 Division and 359th Brigade to quickly move to the Xiaguan to Shentangbao area to wait for concealed aircraft, waiting for an opportunity to destroy an enemy. On the 12th, after more than 800 Japanese troops dispatched from the battalion attacked the south, they retreated northward from the same road and were surrounded by the Eighth Route Army in the area of Kouquan and Changping. After a fierce battle, one of the enemy was wiped out, and the rest used the darkness to break through the encirclement and attempt to withdraw to the battalion through the upper and lower slender waist streams near Shentang Fort. On the morning of the 14th, when the Japanese fled to the upper and lower slender waist streams, they were attacked by the 717th and 718th regiments of the 359th Brigade of the Eighth Route Army. At dawn on the 15th, most of the invading Japanese troops were wiped out. In this battle, more than 500 enemy troops were wiped out, 11 enemies were captured, and the Japanese attempt to encircle was smashed.