color-coordinated street gang
Refers to groups of young people, often delinquents, who dress in the same color, inspired by US street gangs. Strongly associated with Ikebukuro in the late 1990s. Wasei-eigo; not a direct translation of 'color gang'.
wasei-eigo (Japanese-coined English), from color gang
In the late 1990s, color gangs became a social issue in Ikebukuro.
Color gangs are known for all members wearing clothes of the same color.