The Seoul Metropolitan Police Agency has obtained the nicknames of 15-thousand members of the so-called Baksabang chat room on the Telegram messenger service that distributed illegal photos and videos of violent sex acts involving women and minors.

Police are still tracking down all those who took part in the sexually exploitative acts related to the case based on digital information secured from the prime suspect and operator of the chat room Cho Joo-bin.

An official from the police agency said on Monday that so far they've gathered around 15-thousand nicknames of users who were either paid members or accomplices of the illicit chat room. However, they do not have an exact figure yet since the investigation is ongoing.

Police are also looking into other chat groups that may have shared and posted similar videos.