In the 228 Incident, the Fourth Regiment was responsible for pacifically sweeping the northern region and working with other troops to "clear completely" the urban area of Keelung. After the announcement of martial law on March 10th, the Fourth Regiment was responsible for sweeping the countryside north of Hsinchu, with Major General Mu-Tao Chang serving as the commander of the Northern Pacification zone. The original site of the Fourth Regiment was the Hong Chi Hospital, which Dr. Qing-Yue Lin established. Later, the Government of Taiwan took over the establishment of the Rehabilitation Hospital, which served as a treatment center for opium addicts and patients with anesthesia poisoning. After the post-war relocation, the Fourth Regiment of the Military Police was stationed there.