Thousands of Iranians have gathered to demonstrate in Tehran in defiance of a government ban on such assemblies.
Police in Tehran have reportedly fired tear-gas at anti-government protesters who have declared solidarity with like-minded peers in Tunisia and Egypt.
The protesters reportedly chanted Death to dictators and political prisoners must be freed.
Several clashes have been reported around Tehran University and Sharif University, as well as rallies in other Iranian cities, including Isfahan and Shiraz.
According to Al Jazeera, up to 10,000 security forces were deployed to prevent protesters from gathering at Azadi Square, where the marches were expected to converge.
While Iran’s rulers officially supports the Egyptian revolt, the government dismisses the Iranian rallies as political gestures by opposition forces.
Last week, Iranian police put prominent opposition leader (and former Prime Minister) Mir Hossein Mousavi under house arrest.
Mousavi's official website, Kaleme.com, claimed that hundreds of protesters had been arrested, although there has been no independent confirmation.
Another major opposition leader, cleric and former parliament speaker Mehdi Karroubi, is also under ‘de facto’ house arrest, according to reports.
In June 2009, Iran was engulfed by a populist rage after President Mahmoud Ahmadinejad won a disputed election, leading to a crackdown of opponents of the regime.
For all of its empty talk about Egypt, the government of Iran should allow the Iranian people the same universal right to peacefully assemble and demonstrate in Tehran that the people are exercising in Cairo, White House national security spokesman Tommy Vietor said last week.
The President of Turkey Abdullah Gul, who is currently visiting Iran, warned that when leaders and heads of countries do not pay attention to the demands of their nations, the people themselves take action to achieve their demands.