A two-year international operation involving police from Australia, Bulgaria, New Zealand, Thailand and the US and coordinated by Interpol has led to the arrest of nine alleged child sex offenders in Thailand, the US and Australia. 

More arrests are expected, with referrals being examined in nearly 60 countries.

The investigation — called Operation Blackwrist — was launched in 2017 after police found material showing the abuse of 11 boys, all below the age of 13, by an online international pedophilia ring operating on the dark web on a subscription basis. Police say the perpetrators often masked the children's faces, with little audio on the videos that could serve as clues for police.

Dark web sites cannot be found via search engines, and access requires typing in the specific URL address.

Police said 50 children were rescued, with around 100 more suspected of having suffered abuse. The youngest boy was just 15 months old. Police are working to identify the victims.

"Operation Blackwrist sends a clear message to those abusing children, producing child sexual exploitation material and sharing the images online: We see you, and you will be brought to justice," Interpol Secretary-General Jürgen Stock said in a statement.

Read more: German child porn network Elysium founders sentenced

Interpol stressed that international cooperation in fighting child sexual abuse was key as pedophilia networks tended to be "transnational."

First arrests in 2018

In early 2018, police made the first arrests, capturing the site's main administrator, Montri Salangam in Thailand. He was seen abusing the 11 boys, one of whom was his nephew. Another administrator, Ruecha Tokputza, was detained in Australia.

In June that year, a Thai court sentenced Salangam to 146 years in prison for child rape, human trafficking as well as possession and distribution of child sex abuse material. Tokputza was jailed for 40 years in Australia — the highest sentence ever handed down for child sexual abuse in the country.

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