Twelve people including nightclub owners and DJs were arrested for consuming illegal drugs, police said Thursday.

The Yongsan Police Station said it arrested 12 people including two nightclub owners and booked 41 drug users. According to police, a nightclub owner, identified by his surname Kim, smuggled in marijuana and other illegal substances, and sold them to those frequently visiting his club.

They consumed the drugs in clubs located in Itaewon and Sinchon. Police are widening the investigation based on information from scores of other people, mostly children of affluent families who participated in “parties.”