In one of the largest investigations of online child exploitation, authorities have busted 14 men for allegedly running an underground, members-only child pornography ring that exploited more than 250 children.

Two of the children were younger than 3, officials said on Tuesday.

These kids, mostly boys, were from 39 states and five foreign countries, according to  U.S. Immigration and Customs Enforcement.

The investigation, called “Operation Round Table,” was led by ICE, the U.S. Postal Inspection Service and federal authorities in Louisiana, where the alleged leader of the operation lives.

ICE alleges that the secret website’s primary administrator, Jonathan Johnson, 27, of Abita Springs, La., created fake female personas on social media networks to prey on and sexually exploit children.

In a statement, ICE Deputy Director Daniel Ragsdale said:

“Never before in the history of this agency have we identified and located this many minor victims in the course of a single child exploitation investigation. … 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. 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.”

From about June 2012 until June 2013 the website operated on a hidden online network, called Tor, that conceals the user’s location, according to the government.

The alleged porn ring was exposed when someone sent a piece of mail to a child through the U.S. Postal Service. At the time the site was dismantled it contained more than 2,000 webcam-captured videos of boys, according to ICE. It had more than 27,000 subscribers.

Department of Homeland Security Secretary Jeh Johnson, with ICE, U.S. Postal Inspection Service and the U.S. Attorney for the Eastern District of Louisiana announced the results of the Operation Round Table investigation in a press conference on Tuesday.

Last year, more than 2,000 predators were charged criminally in connection with online sexual exploitation of children, ICE reported.