Demilitarized Zone Peace Preservation Corps
The Demilitarized Zone Peace Preservation Corps was a police force created by the Tanggu Truce 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 during the late 1930s . 
<triplet> Great Wall <subj> Hebei <obj> located in the administrative territorial entity <triplet> Hebei <subj> northern China <obj> part of