In February 1941, Thanh Hoa provincial party committee hold a meeting in Phong Coc village, Tho Xuan district) to discuss about the foundation and development of militia and guerilla units, establishment of revolutionary bases in Thanh Hoa. In June 1941, in Phuc Tinh village, Thieu Yen district (now belongs to Yen Thai commune, Yen Dinh district), at the open meeting of Thanh Hoa provincial party committee, it was decided to establish the revolutionary bases and assigned members to be responsible for bases. In July 1941, in the Northeast region, Dang Chau Tue, Dang Van Hy, Trinh Huy Lan (Tran Tien Quan) and Thach Thang district party committee for Anti-Imperialism and National Salvation, did choose Ngoc Trao village to be the base for training guerilla force, set up base’s steering committee including Dang Chau Hue, Dang Van Hy and Trinh Huy Lan.    

On the 19^th September 1941, in Treo Cave (Ha Long commune, Ha Trung district) in the flickering torch-light, under the national flag, Ngoc Trao guerilla unit, the forerunner of the Thanh Hoa revolutionary armed forces, was officially found, including 21 men, divided into three squads and Dang Chau Hue as commander. The first men of Thanh Hoa armed force, did pledge allegiance to revolutionary cause, fight and scarify their last blood for national liberation cause.