Iran's most powerful military force on Wednesday warned online media of a crackdown over their coverage of the country's election crisis.
The Revolutionary Guards, an elite body answering to the supreme leader, said Iranian Web sites and bloggers must remove any materials that "create tension" or face legal action.
It is the Guards' first public statement since the crisis erupted following the presidential election last Friday.
Iranian reformist Web sites as well as blogs and Western Web sites like Facebook and Twitter have been vital conduits for Iranians to inform the world about protests over the declaration of election victory for hardline President Mahmoud Ahmadinejad.
The government barred foreign media Tuesday from leaving their offices to report on the street protests.