Officials in the US say 72 people from 14 countries have been apprehended for their involvement in a child pornography network.
They have been charged with participating in sharing photos and videos of the sexual abuse of children, as part of a website known as 'Dreamboard'.
Officials say around 600 people used the site in total.
US Homeland Security Secretary, Janet Napolitano, said that it is child porn on an industrial scale.
"The board may have been the vehicle of 123 terabytes of child pornography, which is roughly equivalent to nearly 16,000 DVDs," she said.