1939 April 13 At 4: 50 p.m., the air defense alarm rang through Mengzi. The first batch of19 Japanese planes that took off from Nanning invaded Mengzi from Gejiu, bombarded the county town and strafed at low altitude, dropping more than 100 bombs and flying off Dongshan. Half an hour later, the second batch of four planes suddenly flew back from Dongshan, because the citizens of the county had never been attacked by air. One is to mourn the people killed in the air raid in the city, the other is to test the civil air defense equipment, and the third is to carry out national defense education.