A 25-year-old South Korean who masterminded one of the world’s largest online sexual blackmail rings was sentenced to 40 years in jail on Thursday after being found guilty in a case which sparked national outrage.
Prosecutors had sought life term for Cho Ju-bin, saying his crimes were "unprecedented in history". Other associates in the ring were sentenced to imprisonment from seven to 15 years.
Cho was found guilty of blackmailing at least 74 people, including 16 minor girls, into providing sexually compromising images and videos, and hosted chatrooms where at least 10,000 people watched the explicit content.
"The accused has widely distributed sexually abusive content that he created by luring and threatening many victims," Yonhap news agency quoted the Seoul Central District Court as saying on Thursday.
An investigation was launched into the case after two university journalism students found the groups on Telegram last summer.
In March, the 25-year-old college graduate was arrested and his name was made public by the police in an unusual step after five million people signed petitions demanding his identity be revealed.
The judge ruled on Thursday that he was also guilty of “instructing a third party to directly rape a victim, who was a minor".
Apart from 40 years in jail, Cho was fined 10.64 million Korean won (£7,200) and ordered to undergo round-the-clock monitoring by wearing an electronic ankle bracelet for 30 years after his release from prison.
The Korean government began using electronic anklets in 2008 to monitor those convicted in sex crimes.
Police arrested about 124 suspects in the case, including 8 operators of chatrooms on Telegram and other social media in March.
The verdict has led to a flurry of reactions from people in South Korea, with some praising the decision while others demanded life imprisonment.
"I apologise to those who were hurt by me," Cho had said in March as he was led away from a Seoul police station. "Thank you for putting a brake on the life of a devil that could not be stopped."