Riot Police Unit

Riot Police Units (機動隊, Kidō-tai^?) are riot police forces and general reserves of Japanese prefectural police forces. These units were formed to respond quickly and effectively to large public disturbances, disaster relief, or other emergency situations as the core of Japanese law enforcement for crisis management throughout the country.

In the pre-war era, the Tokyo Metropolitan Police Department (TMPD) established the Special Security Unit (特別警備隊, Tokubetsu-keibi-tai^?). During the war, in conjunction with other prefectures, this unit was changed to the Security Unit (, Keibi-tai^?), but was disbanded in 1946.

On the same day, the Guard section (防護課, Bougo-ka^?) was created for the same role in the TMPD. In 1948, this unit was reinforced to the Police Reserve Units (予備隊, Yobi-tai^?). These civilian police corps worked as a rapid reaction force to maintain public order against large-scale violence or other incidents. In 1957, their name was changed to the Riot Police Units. Until 1962, all Prefectural Police Departments had the same kind of units.

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