Police have smashed a global Internet pedophile ring with 700 members and rescued more than 30 children from abuse, a police spokesman said on Monday.
Detectives targeted an Internet chatroom where members from 35 countries swapped thousands of indecent pictures and films of children.
Undercover officers gathered evidence at the site, called "Kids the Light of Our Lives", before arresting its host, Timothy Cox, 28, from Suffolk.
Police found nearly 76,000 explicit images and 1,100 videos on his computer. He supplied thousands of pictures to others, using the online name "Son of God".
Cox pleaded guilty to charges of possession and distribution of indecent images of children and is due to be sentenced at Ipswich Crown Court this week.
The Child Exploitation and Online Protection Centre (CEOP), which led the investigation, said the case was a "powerful warning" to pedophiles.
"Any individual who thinks they carry out such horrific activities undetected is in for a very rude awakening," said CEOP Chief Executive Jim Gamble. "The belief that the Internet provides anonymity is unfounded."
Cox was arrested after Canadian police passed information to their British counterparts last summer.
Officers from Britain, Canada, the United States and Australia took part in the investigation.
Police identified 700 members of the site, including 200 in Britain, while 31 children have been rescued from abuse, CEOP said.
A second man who tried to revive the site after Cox's arrest was arrested in January.
Gordon Mackintosh, 33, from Hertfordshire, had 5,000 explicit images of children on his computer. He used the online nicknames "Silent Black Heart" and "Lust4skoolgurls".
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