Iran's opposition has come out in force to mount some of the biggest street protests since June's disputed elections in an attempt to overshadow official rallies marking the 30th anniversary of the storming of the US embassy in Tehran.

Thousands of demonstrators poured into the capital to defy riot police, revolutionary guards and Basij militiamen wielding clubs and kicking protesters, as well as firing teargas and – according to some unconfirmed reports – bullets.

Video footage on the internet showed supporters of Mir-Hossein Mousavi, who claims he won the presidential race, stamping on images of Ayatollah Ali Khamenei, Iran's supreme leader, and denouncing him as a "murderer". Others criticised the president, Mahmoud Ahmadinejad. Many wore wearing green scarves, ribbons or wristbands.

At the same time, government supporters burned US flags to commemorate the 1979 embassy takeover – a pivotal moment in the Iranian revolutionary calendar. But shouts of "death to the dictator" were audible on state TV during live coverage of the official ceremony.

In Washington, Barack Obama marked the anniversary by calling on Tehran to make concessions over its nuclear programme, "turn the page" on the past and forge a new relationship with the US. "Iran must choose," Obama said. "We have heard for 30 years what the Iranian government is against; the question now is what kind of future it is for."

The last big demonstrations in Iran were in mid-September when the opposition also tried to hijack an official event – the annual al-Quds day celebration expressing solidarity with the Palestinians – safe in the knowledge that the authorities would not want to cancel it for fear of trouble.

It is difficult to estimate crowd numbers because of restrictions on independent media. Most non-Iranian journalists were thrown out shortly after the election and those who remain are not free to report.

There were credible reports of protests from Shiraz, Isfahan and Rasht.

Witnesses said the security forces behaved more brutally than in September. "I've never seen such violence," a woman in Haft-e-Tir Square told Persian Radio. "They chased us down a dead end. We were all crushed together and the riot police shot something like five teargas canisters into the alley."

Zeynab, 22, a Tehran University student, said: "We started our protest very peacefully but riot police attacked us with batons and teargas on our way in Vali-e-Asr street. I saw people who were bleeding badly from the head."

Film clips showed fires in the streets and demonstrators chanting "A green Iran doesn't need nuclear weapons."

Mousavi and Mehdi Karoubi, another defeated reformist candidate for the presidency, had urged their supporters to take to the streets to protest against Ahmadinejad and maintain pressure on the regime. Mousavi was barred from leaving his home. Karroubi briefly joined protesters in Haft-e Tir Square, according to the Mowjcamp reformist website.

Speaking before Obama's message, Grand Ayatollah Hossein Ali Montazeri, a senior religious leader and critic of the government, called the seizure of the US embassy in 1979 a mistake. "The occupation of the American embassy at the start had the support of Iranian revolutionaries and the late Imam Khomeini [Iran's former supreme leader] and I supported it too," said a statement posted on his website. "But considering the negative repercussions and the high sensitivity which was created among the American people and which still exists, it was not the right thing to do."
 

Source: http://www.guardian.co.uk/world/blog/2009/nov/04/iran-student-day-protests