Demilitarized Zone Peace Preservation Corps
The Demilitarized Zone Peace Preservation Corps was a police force created by the 1933 Tanggu Truce between China and Japan in the aftermath of the Japanese invasion of Manchuria. Its role was to patrol and maintain order in the demilitarized zone extending from south of the Great Wall, to a line north east of the Bai River in Hebei province in northern China.
Source: Wikipedia — Demilitarized Zone Peace Preservation Corps (CC BY-SA 4.0)