Child rapist sought by US over net porn ring

More than 50 people had been arrested since the 2008 start of the investigation, US Attorney Tim Morrison said.

Authorities said they were seeking the extradition of several suspects, including the group's alleged ringleader, Delwin Savigar, 35, of Leyland, Lancashire, who is serving a 14-year prison term in Britain for sexually assaulting three underage girls, Mr DeBrota said.

Savigar created and ran a password-protected website from which members could access collections of sexual images – some including as many as a million files – share their fantasies about having sex with children and give advice to each other about how to build their collections and avoid getting caught, according to US officials who claim it is the largest child abuse case ever brought.

One suspect, 47-year-old Edward Oedewaldt, who was arrested on April 23 in Louisiana, was brought to Indianapolis yesterday to face charges of conspiracy to advertise and distribute child pornography and was remanded in custody until his trial. He has pleaded not guilty.

Prosecutors said 35 ring members had been convicted on child porn charges. Some of them had received sentences of up to 20 years in prison.