The Sanmu incident (三無事件, San mu jiken) was an attempted coup d'état in Japan that was foiled on December 12, 1961.
The stated goals of the group were to kill Prime Minister Hayato Ikeda, his Cabinet, and take control of the National Diet.
At the time of the arrest, the conspirators had already come into possession of uniforms and deadly weaponry, such as grenades and rifles.
[1][2] Amongst the members were officers of the former Imperial Japanese Army, such as Major General Tokutaro Sakurai.
Also involved were businessman Toyosaku Kawanami and former Manchukuo minister of economic affairs Han Yunjie [jp].