By Graham Satchell In Washington

The FBI has broken up an international child pornography ring, arresting more than 80 people in 20 states across America.

The US attorney general, John Ashcroft, said among those charged were Catholic priests, a police officer, a nurse and a school bus driver.

Attorney General Ashcroft: Targeting "dark corners of cyberspace"

The US Justice Department has described this investigation as the most significant crackdown ever attempted against child pornography.

Eighty-nine people have been arrested and charged with receiving and transmitting graphic sexual images of children over the internet.

The FBI investigation began 14 months ago when an undercover agent in Houston discovered three message groups.

'Pillars of the community'

Since then there have been more than 230 searches in 20 different states. One suspect in Little Rock, Arkansas, committed suicide.

One of the most shocking aspects of this case is that the people arrested have been described as pillars of the community. Little league coaches, foster care providers, priests - even judges are currently under investigation.

The Attorney General, John Ashcroft, said this was not only about trading images - evidence had also emerged of abuse.

Twenty-seven of those so far arrested have admitted to molesting children. More arrests are expected in the future.

One of the internet sites which has now been shut down had an estimated 7,000 members - more than 2,000 of them outside the US.