Seikijuku (正氣塾, "Sane Thinkers School") is a right-wing Japanese imperialist group based in Nagasaki Prefecture, founded in 1981. The group was responsible for a number of violent incidents, including the 1990 near-fatal shooting of the mayor of Nagasaki Hitoshi Motoshima who stated that Emperor Hirohito was responsible for the war.
References
Seikijuku Wikipedia(Text) CC BY-SA