The Toa-kai, formerly known as the Tosei-kai, is a Korean yakuza syndicate based in Tokyo. The group was formed by Hisayuki Machii in 1948, and it was originally a far-right organization of anti-communist activism that sympathized with Kanji Ishiwara and was in conflict with the pro-North Korean Chongryon. The Tosei-kai quickly became one of Tokyo's most powerful gangs, with membership reaching 1,500 in the 1960s. In 1965, increased crackdowns forced Machii to disband the Tosei-kai and establish the Toa-kai. The Toa-kai became a member of the Kanto Hatsuka-kai bakuto fraternal federation alongside the Sumiyoshi-kai, Inagawa-kai, Matsuba-kai, and Soai-kai, and it allied with the Yamaguchi-gumi. The Toa-kai has its headquarters in Ginza, once the gang's stronghold.