Although the Interior Ministry banned rallies in the capital, tens of thousands of Mousavi supporters wearing green bandanas and waving green flags took to the streets in response to their candidate’s call for “peaceful” protest.

Many have been surprised by Khamenei’s decision because he was the first one to declare Ahmadinejad the winner, even before the Interior Ministry, calling the outcome a “divine blessing.”

The 12-member Guardian Council will now take over and examine the complaint. Under Iranian law the council supervises the electoral process and the constitution, but is also know for its literalist interpretation of Islam and its arch-conservative positions.

Since Ahmadinejad’s victory was announced Mousavi supporters, young and old, have poured into the streets of Tehran and other cities. Sporadic clashes with police have been reported. 

Overnight anti-riot police and pro-Ahmadinejad vigilantes clashed with students at Tehran University, using tear gas and plastic bullets. Students responded with slogans, stones and Molotov cocktails.

Tens of students were arrested and police seized computers and other electronic equipment.

A website close to Mousavi reported that a student protester was killed early Monday during clashes with plainclothes hard-liners in Shiraz.

Hundreds of pro-Mousavi supporters have felt the regime’s iron fist, including a brother of former moderate president Khatami.

Mass media have also been affected by the crackdown. Foreign reporters are not being allowed to film demonstrations. Some have been arrested. TV and radio broadcasting out of Iran have been disrupted. Satellite communications and some websites have been blocked.

As for Mousavi, who served as prime minister during the 1980s, the defeated candidate has threatened to hold a sit-in protest at the mausoleum of the late Ayatollah Ruhollah Khomeini, founder of the 1979 Islamic Revolution.

In an interview with Iranian movie director Mohsen Makhmalbaf, published in the Persian-language webzine Rooz, Khamenei’s decision to give the victory to Ahmadinejad amounts to a “coup”.

Makhmalbaf, who on Election Day was in contact with Mousavi’s election headquarters, said that according to the Interior Ministry Mousavi had won. He added that the latter had in fact worked on a moderate victory speech.

Information about Mousavi’s victory was also provided to Supreme Leader Khamenei. Just a few hours later revolutionary guards showed up at Mousavi’s election headquarter with a letter from Khamenei, which said that he would not let the green revolution succeed because “Ahmadinejad’s defeat is my defeat.”