A yakuza organization based in Kyoto, Japan, founded in 1868 by Senkichi Kousaka. Its name derives from the Aizu region and 'Kotetsu', a type of Japanese sword. In 1992 it was among the first syndicates designated under Japan's anti-boryokudan laws, and it challenged the legislation in court. At its peak in 1993 it had 1,600 members, but membership has since declined to about 40.
CRIMENET has extracted 2 linkages for this organization, including 2 cooperative ties across 1 organization.