We all know about soviet NKVD blocking detachment and from what I read on this sub they were mostly just there to stop them from retreating by arresting them, not the exaggerated summary execution shown on TV and films.
I recently read that the NRA (National Revolution Army) had those as well in China during the early 20th century. Most stories regarding these blocking detachment are from 1937, during the 2nd Shanghai Incident, where retreating Chinese soldiers were shot and entered combat with these blocking detachments.
Are these real or just PR products like the NKVD?
Here's a picture of a flag of the blocking detachment that I've found on wikipedia.
Can any Chinese expert chime in and tell me what they know of these blocking detachments, 督戰隊?
That picture just appears to be the Northeastern Army's 15th military police brigade. The NRA's military police detachments served partly as military police and partly as political troops like the NKVD and the Kempeitai. There was at least one unit committed to Shanghai for morale purposes: however most of the NRA troops committed to Shanghai were well-trained front-line troops, not the conscript forces one typically associates with blocking detachments. Often times though there were incidents where deserting Chinese troops turned brigand to secure supplies and had to be put down by the military police or even regular units.
edit: That being said, blocking detachments and similar tactics are hardly anything new in Chinese military tactics. The rather famous phrase 破釜沉舟 (Break the kettles and sink the boats, i.e., destroy all impediments for retreat) being a prime example.
