The Internet service provider was approached by the National Crime Squad and agreed to allow officers to access its servers. This led to the recovery of data showing the activity of nearly 1,500 newsgroups during a two-week period.
From this data, officers established that almost 10,000 Internet Protocol (IP) addresses had accessed more than 30 of the Web sites carrying paedophilia. For operational reasons this number was whittled down to just over 400 addresses of those specifically distributing paedophiliac images.
The information was then distributed via Interpol to the countries identified with the suspects, and evidence packs on each of the targets were distributed to the relevant police forces
Detective Superintendent Peter Spindler, leading the investigation for the National Crime Squad, said: "With the assistance of Demon Internet and the support and guidance of the National High-Tech Crime Unit, we are able to show that those accessing these newsgroups did so regularly and with purpose.
"We also learnt, not surprisingly, that those abusing the Internet have learnt from recent police successes how best to protect their true identities," he added.
The National Crime Squad and Serco, its IT partner, have developed facial mapping software that they hope to use to identify the abused children featured on the paedophiliac sites.