Police said the breakthrough was the result of a three year investigation involving police around the world [Reuters]

Police from around the world have arrested 184 suspected members of a major paedophile ring and rescued 230 children from abuse, the European Union's police agency has said.

Europol said it had identified 670 suspects in the ring, which centred on a Dutch-based website, following a three-year investigation that involved police from Europe, the US, Australia and Thailand.

"We expect these numbers to rise further," Rob Wainwright, director of the policy agency said at a press conference in The Hague, the Netherlands, on Wednesday.

"This is already the biggest case of its kind we have ever seen."

The online forum boylover.net, which has since been taken down and its operator taken to court, promoted sex between adults and boys, police said.

"The website attempted to operate as a discussion-only forum where people could share their sexual interest in young boys without committing any specific offences and operate below the radar," Peter Davies of Britain's Child Exploitation and Online Protection Centre told the press conference.

But he said many members had moved onto email to exchange and share illegal images and films of children being abused.

Those detained by police include teachers, police officers, scout leaders, at least one woman and an 84-year-old man.

One suspect arrested in Spain is said to have worked with children at a summer camp and is suspected of abusing more than 100 children over five years.

Although most of the suspects abused children close to them, the suspects did not share a specific profile.

"There is no particular rule about the age, there is no particular rule about the walk of life they are in. There is no particular profile of someone who is a threat to children in this way," Davies said.

He said it was likely that there would be more arrests as investigations continue.

"Those who have been members of the site can expect a knock on the door in the very near future," he said.