WASHINGTON — Fourteen men have been charged with operating a child pornography website with 27,000 members and more than 2,000 videos, federal law enforcement officials said Tuesday.

The investigation, one of the largest online child exploitation probes ever launched by U.S. Immigration and Customs Enforcement, found 251 victims in 39 states and five foreign countries.

Additional Photos Daniel Ragsdale, left, deputy director of U.S. Immigration and Customs Enforcement, discusses the results of an international investigation of a child pornography website. The Associated Press

In most cases, young boys were targeted online by the men and tricked into creating sexually explicit videos of themselves.

“Operation Round Table,” the name given to the investigation, started with the June 2013 arrest of the network’s alleged creator, Jonathan Johnson, 26. According to the statement, he acknowledged enticing young boys by assuming female personas on social networks and pressing other men to follow suit.

Most victims were male between 13 to 15 years old, officials said. Two victims were 3 years old or younger.

In a news conference Tuesday, Secretary of Homeland Security Jeh Johnson said the alleged perpetrators targeted “the most innocent, most vulnerable members of our society with no regard for the immediate or lasting harm they cause to the victims and their families.”

Led by ICE and the U.S. Postal Inspection Service, the investigation identified victims in Britain, Canada, New Zealand, Australia and Belgium.

From June 2012 until June 2013, the child pornography site operated on Tor, an underground network that directs Internet traffic through relays to ensure user anonymity.

As authorities pour through more than 40 terabytes of data, they say more arrests are likely. Officials also cited more than 300 open investigations into possible website subscribers.

In addition to Johnson, authorities have charged 10 men in the Eastern U.S. District of Louisiana believed to be largely responsible for running the scheme and producing pornographic materials. Three men were also charged in Colorado, New York and Wisconsin.

While ICE Deputy Director Daniel Ragsdale said arrests play a vital role, he also said law enforcement must employ other strategies to curb an increase in child exploitation.

“Our agency is seeing a growing trend where children are being enticed, tricked and coerced online by adults to produce sexually explicit material of themselves,” Ragsdale said in a written statement. “While we will continue to prioritize the arrest of child predators, we cannot arrest our way out of this problem: Education is the key to prevention.”

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