In brief: The Justice Department has announced that law enforcement agents from the US, South Korea, and the UK have taken down the largest child pornography site on the dark web.

The notice states that a federal grand jury in the District of Columbia has indicted Jong Woo Son, a 23-year-old Korean national, for his operation of Welcome To Video, the largest child sexual exploitation market by volume of content. Son was charged in August 2018, but the indictment was only unsealed Wednesday.

Son is already serving a sentence in South Korea after being charged and convicted of operating the site, which contained over 250,000 unique videos - over eight terabytes - involving child sexual exploitation. Forty-five percent of the videos currently analyzed contain new images that have not been previously known to exist.

According to the DoJ, Welcome to Video was one of the first websites of its kind to monetize child exploitation videos using bitcoin. Each user received a unique bitcoin address when they created an account on the website, and the site had capacity for at least one million users.

Law enforcement officials were able to identify the site administrator and the server's South Korea location by tracing the bitcoin transactions, which involved following the flow of funds on the blockchain.

More than three-dozen other individuals involved with the site have also been arrested and charged, as have 337 site users from across 24 US States and 11 countries.

The DoJ added that the operation saw the rescue of at least 23 minor victims residing in the United States, Spain, and the United Kingdom, who were being actively abused by the users of the site.