Police said today that the men fired several shots at the General Association of Korean Residents in Japan, a pro-Pyongyang group representing ethnic Koreans in Japan.
They said the men, aged 46 and 56, drove by in a vehicle and one of them fired several shots. The gate was damaged but nobody was injured.
Police said their motive was not known.
Patrolling police rushed to the closely monitored organisation and arrested the man on the spot, confiscating a gun.