Kazakhstan’s law enforcement agencies have dismantled three underground drug laboratories in Almaty, with seven members of an organized criminal group sentenced to 16 years in prison.

Police, acting in coordination with the Medeu District Prosecutor’s Office, shut down the clandestine facilities, which were producing psychotropic substances in especially large quantities. The laboratories were reportedly located inside private residential homes, The Caspian Post reports via Kazakh media.

Authorities seized a significant volume of narcotics from illegal circulation, including mephedrone, a synthetic stimulant widespread on the black market.

Seven members of the criminal group were detained and each received a 16-year prison sentence. The organizer of the operation managed to flee and has been placed on an international wanted list.