Crimes committed by tokuryū, loosely connected anonymous groups that primarily operate through social media, have become a serious social issue in Japan.

They are often linked to special fraud schemes, social media-based scams and violent robberies carried out by individuals lured into illicit part-time jobs, or yami baito.

Police have made capturing the ringleaders a top priority but are struggling in their investigations, largely due to the criminals' use of highly encrypted communication apps.