Officials arrested 337 individuals around the world, following an international investigation into a dark web child pornography site that sold illegal videos for untraceable digital currencies.

Authorities also rescued 23 underage victims from active abuse in the United States, Spain and Britain following the crackdown on users of the South Korea-based site "Welcome to Video."

Law enforcement agencies from the US, UK and South Korea jointly described the operation as one of the largest into child pornography networks they have tackled to date, with those arrested being from 12 different countries.

Following the take-down of the site in March 2018, authorities concentrated on uncovering the identities of site users.

The site's operator, the 23-year-old Jong Woo Son from South Korea, was also charged with nine counts related to the operation of the site.

He is already serving an 18-month sentence in South Korea on convictions related to child pornography.

"These are the bottom feeders of the criminal world," said Don Fort, chief of criminal investigation at the US Internal Revenue Service, which initiated the investigation along with the British National Crime Agency (NCA).

"The website monetized the sexual abuse of children and was one of the first to offer sickening videos for sale using the cryptocurrency Bitcoin," the NCA said in a statement.

Read more: German authorities turn to AI to combat child pornography online

Users paid in cryptocurrency

The site allowed users to pay for the hundreds of thousands of child pornographic videos using the Bitcoin cryptocurrency, allowing users a degree of anonymity online.

Investigators viewed the hundreds of arrests as a success for authorities in their battle against illegal sites, which use cryptocurrencies because of their presumed anonymity and ability to render purchasers untraceable.

"You went on the dark web, thinking that your actions were anonymous, but they weren't, and we found you," Fort said of the site's users at a press conference.

The US Justice Department said the site collected at least $3.7 million (€3.3 million) worth of Bitcoin between June 2015 and March 2018 when it was taken down.

kmm/sms (Reuters/AFP)

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