The special Guards unit for fighting organized Internet crimes announced in late March that its task force had closed down 90 porn sites and has regularly updated the details of the operation by publishing and broadcasting what it says are the confessions of the people accused of managing the sites.
The arrestees have been accused of promoting orgies and incest, illegally uploading sex clips of young girls and ridiculing Shia Islamic beliefs, and include at least two Iranian men and one woman who used to live abroad, but whose friends say were tricked into coming home and then arrested.
Some were caught after their emails were intercepted by the task force, says Ali Rahnama, a journalist in Tehran quoting sources close to the operation.
Although access to porn websites is blocked in Iran, many people manage to access them. One of the porn sites involved in the arrests had 300,000 registered Iranian users and some of the adult video clips were downloaded at least 6 million times, according to the Guards.
With a population of more than 70 million, Iran has 12 million Internet users, and experts have said that in a mainly traditional society like Iran, the Internet has revolutionized young people's lifestyle so dramatically that some hardliners, including conservative bloggers, have called for much tougher regulation and policing of the web.
A blogger supporting Iran's hardline president Mahmoud Ahmadinejad has called porn sites the Trojan horse of his country's Western enemies and urged the government to combat them.
