Iran has arrested 53 suspects and shut down 132 websites linked to the Islamic State group since April 2014, the country's cyber police chief said on Monday, according to state media.
"The cyber police has been identifying and removing web pages exclusively owned by Daesh or people who in some way supported them and advocated their ideologies," Brigadier General Kamal Hadian, using the Arabic acronym for IS, was quoted by official news agency IRNA as saying.
The general did not specify if the pages were online profiles or entire websites and how many detentions had been detected recently.
"We have arrested 53 inside the country," Hadian said of the suspects, adding that "some of the deceived ones were released after signing a pledge" to cease such activities.
Iran, sharing borders with Iraq and Afghanistan, faces the threat of attacks and recently beefed up security in Tehran and other cities, with armed police outside some metro stations and public squares.
Iran, a predominantly Shiite country, has been involved in the fight against the Sunni extremists of IS in Iraq and Syria, providing the governments in Baghdad and Damascus with financial and military help.
The cyber police chief said the websites linked to IS and terror networks were mostly operating near Iran's borders.
More than a 100 foreign-based websites were also referred to international police for removal, he said.
Iran arrested members of a jihadist cell linked to IS near its western borders with Iraq, the head of the country's Revolutionary Guards said on November 22.
After the deadly IS attacks in Paris last month, IS threatened to attack Iran. The special armed police were deployed in Iran's major cities shortly afterwards.
Security officials, however, maintain that the police presence is part of a drill and not a response to a specific threat.