Federal authorities said Wednesday that a South Korean national and hundreds of other individuals worldwide were charged with operating or using a major dark web child sexual exploitation site that included videos of adults abusing children as young as 2 years old.

A nine-count indictment says 337 people in 24 U.S. states and 11 countries, including eight individuals in the Washington, D.C., area, were arrested and charged with operating or using the site.

The Department of Justice said two users of the site died by suicide after the execution of search warrants.

The dark web, also known as "darknet," refers to encrypted online content that is not indexed by conventional search engines.

“Darknet sites that profit from the sexual exploitation of children are among the most vile and reprehensible forms of criminal behavior,” said Assistant Attorney General Brian Benczkowski of the Justice Department’s Criminal Division.

Prosecutors, who announced the unsealing of a sweeping indictment, said authorities seized approximately eight terabytes of child sexual exploitation videos, which they called one of the largest seizures of its kind.

Authorities said the site contained 250,000 videos that were downloaded a million times by users worldwide.

The indictment says the site carried numerous graphic videos depicting adults engaged in sexual acts with children as young as 2 years old. Viewers could use a search engine to pick videos by age, including "preteen hardcore" and "pedophile."

At least 23 young victims abused by the site's users were rescued in the USA, Spain and the United Kingdom.

The National Center for Missing and Exploited Children (NCMEC) analyzed the site's content, including more than 250,000 unique videos, according to the Department of Justice.

The indictment, issued in the District of Columbia, charges that the Welcome to Video site was run by Jong Woo Son, 23, a South Korean national.

Users, who could view videos and upload their own, paid for the service with hard-to-trace bitcoin. Users earned "points" by uploading their own porn images and videos.

South Korean authorities arrested Son and seized his server in 2018, shutting down an operation active since at least June 2015.

Son was convicted in 2018 and is serving a sentence in South Korea. The indictment unsealed Wednesday not only lists his name and U.S. charges against him, it also announced the intent by federal authorities to seize the images and any proceeds and property linked to the operation.

The federal complaint says undercover agents traced payments of bitcoin to the darknet site.

The indictment says authorities got a break in their investigation in 2017 when they found that the source code for the website's home page failed to conceal an IP address that led back to South Korea.

Several of those named have already been convicted of related crimes. Among those was Kyle Fox, 26, of the United Kingdom, who was sentenced to 22 years for raping a 5-year-old boy and appearing on Welcome To Video sexually abusing a 3-year-old girl.

Also named was Richard Nikolai Gratkowsi, 40, of San Antonio, a former agent for Homeland Security Investigations, who pleaded guilty to receiving child pornography and one count of access with intent to view it. He was sentenced to 70 months in prison.