Iranian riot police clashed with supporters of Iran's opposition leader Mirhossein Mousavi on Wednesday as the country marked the 30th anniversary of the storming of the US embassy in Iranian capital Tehran.

Witnesses said the violent clashes occurred at Haft-e-Tir square in the heart of the Iranian capital.
 

"Police clashed with hundreds of anti-government protesters. They were chanting 'Death to dictators'. Police used batons to disperse them," a witness told the Reuters news agency.

Another witness said police fired teargas at the crowd.

Opposition leaders Mousavi and Mehdi Karoubi had urged their supporters to take to the streets to stage peaceful protests against the government of President Mahmoud Ahmadinejad.

"There are hundreds, chanting 'God is greatest'. Police and Basij militia are outnumbering the protesters," the witness said.

Iran's Revolutionary Guards and its allied Basij militia had warned the opposition to avoid using any anti-US rally to revive protests against the clerical establishment after June's disputed presidential election, in which Ahmadinejad secured a second term.

The unrest that erupted in the wake of  vote was the worst Iran had witnessed in the past three decades.

The authorities deny vote rigging, and have portrayed the unrest as a foreign-backed bid to undermine the Islamic state.

Remembering the storming of the US embassy

The protests coincided with rallies to mark the 30th anniversary of the storming of the US embassy in Tehran. Huge crowds descended on the embassy complex in central Tehran, chanting "Death to America" and "Death to Israel" and smashing posters of America's “Uncle Sam”.

By Florence VILLEMINOT

US President Barack Obama, who has made diplomatic overtures towards Tehran since he came to power one year ago, urged Iran to look to the future rather than the past.

"We have heard for 30 years what the Iranian government is against; the question, now, is what kind of future it is for," he said.

Leading Iranian dissident cleric Grand Ayatollah Hossein Ali Montazeri said meanwhile that the capture of the US embassy was a mistake.

"The occupation of the American embassy at the start had the support of Iranian revolutionaries and the late Imam Khomeini and I supported it too," he said.

"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," Montazeri said in a statement posted on his website.

Some leaders of the student militants who seized the US embassy shortly after Iran's 1979 Islamic revolution, along with dozens of moderate political figures, have been imprisoned since the election in June.