The South Korean site adopted digital currency to access the video, with victims rescued in the US, UK and Spain

Hundreds of people have been arrested in a worldwide operation over a South Korean dark child sex abuse website that sold videos for digital money.

Officials from the United States, Britain and Korea described the network as one of the largest operations they have encountered to date.

Called Welcome to video, the website relied on the cryptocurrency Bitcoin to sell access to 250,000 videos depicting child sexual abuse, authorities said, including footage of extreme abuse of young children. Its download page specifically said, ” Don’t download adult porn.”

“Darknet sites that profit from the sexual exploitation of children are among the most vile and reprehensible forms of criminal behavior,” said assistant U.S. attorney General Brian Benchkowski.

Officials rescued at least 23 juvenile victims in the United States, Britain and Spain who were actively abusing users of the site, the justice Department said. Many of the children in the video are still unidentified.

The site’s extensive library – nearly half of which consists of images never seen by law enforcement-is an illustration of what authorities say is an explosion of sexual assault content online. In a statement, Britain’s National Crime Agency said officials were seeing “increases in severity, scale and complexity”.

Welcome to the video operator, a South Korean named Jeong Woo Song, 23, and 337 users in 12 different countries, have been charged so far, authorities said.

The son, who is currently serving an 18-month sentence in Korea, was also indicted on Federal charges in Washington.

Several others charged in the case have already been convicted and are serving prison sentences of up to 15 years, according to the justice Department.

Welcome To Video is one of the first sites to monetize child sexual abuse using Bitcoin, which allows users to hide their identity during financial transactions.

Users were able to redeem digital currency in exchange for “points” that they could spend downloading videos or buying anything you can watch ” VIP ” accounts. Points can also be earned by uploading images of child sexual abuse.

“These are the bottom feeders of the underworld,” said don Fort, chief of criminal investigation at the U.S. internal revenue Service (IRS), who initiated the investigation.

The justice Department said the site collected at least $ 370,000 before it was taken down in March 2018, and that the currency was laundered through three unnamed digital currency exchanges.

Fort said the investigation was prompted by a recall to the IRS from a confidential source. However, Britain’s National Crime Agency said it came across the site during an investigation into a British academic who in October 2017 pleaded guilty to blackmailing more than 50 people, including teenagers, into sending him images that he shared online.

In a statement, British authorities said the National crime Agency’s cybercrime unit had deployed “special capabilities” to locate the server.

The justice Department gave a different explanation, saying that the Welcome to Video site had leaked the South Korean Internet Protocol of its server address to the public Internet.