An alleged web paedophile ring based in Britain with more than 300 members worldwide has been uncovered after an international police operation.
Ceop is still trying to trace some of the suspects
The UK-based Child Exploitation and Online Protection Centre (Ceop), which led the inquiry, said a number of children had been rescued from abuse.
The key suspects were from the UK and a number of arrests had been made, Ceop chief executive Jim Gamble said.
Officers from Australia, Canada and the US also took part in the operation.
Mr Gamble said Ceop had "identified an online area used by individuals with a deviant interest in children - in my mind that's a paedophile ring".
He said they had managed to infiltrate the ring with help from their overseas counterparts.
"We closed what we believe was a paedophile ring with excess of 300 members," he said.
Michelle Elliot, from the anti-abuse charity Kidscape, praised Ceop and said the arrests were a "significant and very good development".
"In this particular case we ought to be loud and clear about saying that this is good work and this will keep more children safe," she said.
Ceop is a government agency affiliated to the Serious Organised Crime Agency.