Gangs in San Francisco

, also known as , or simply the Japanese Mafia, are members of transnational organized crime syndicates originating in Japan. The Japanese police and media (by request of the police) call them , while the yakuza call themselves . The English equivalent for the term yakuza is gangster, meaning an individual involved in a Mafia-like criminal organization.

Mara Salvatrucha (; ), commonly known as MS-13, is an international criminal gang that originated in Los Angeles, California, in the 1980s. Originally, the gang was set up to protect Salvadoran immigrants from other gangs in the Los Angeles area. Over time, the gang grew into a more traditional criminal organization. MS-13 has a longtime rivalry with the 18th Street gang.

inmate organization

Norteños (, ; Norteñas for females) are the various affiliated gangs that pay tribute to Nuestra Familia while in California state and federal correctional facilities. Norteños may refer to Northern California as ''''. Their biggest rivals are the Sureños from Southern California. As of 2008, the statewide north–south dividing line between Norteños and Sureños was regarded as running through the southern end of the Central Valley. The gang's membership consists primarily of Mexican Americans.

Chinese American Triad Society