Mousavi supporters clash with police in Tehran

TEHRAN (Reuters) - Police clashed with supporters of Iran's opposition leader Mirhossein Mousavi in Tehran on Wednesday when a rally marking the 30th anniversary of the storming of the U.S. embassy turned violent.

Reformist website Mowjcamp said police opened fire on protesters at Haft-e Tir square but there was no independent confirmation of the report.

"Some people were injured," Mowjcamp said, reporting other protests in the cities of Shiraz and Rasht.

Iran's Revolutionary Guards and the allied Basij militia had warned the opposition not to try to hijack an annual anti-U.S. rally to revive protests against the clerical establishment after June's disputed presidential election.

"Police clashed with hundreds of protesters. They were chanting: 'Death to dictators'. Police used batons to disperse them," a witness said. People traditionally chant, "Death to America" at the annual state-organized rally.

By evening the crowds had dispersed but police and Basij maintained patrols on the streets. Mowjcamp reported the arrest of at least 23 protesters in Tehran and the northern city of Rasht by Iran's security forces.

The crackdown showed no compromise from the leadership, underlined by Supreme Leader Ayatollah Ali Khamenei's recent comment that it was a crime to question the June 12 vote which secured the re-election of President Mahmoud Ahmadinejad.

Defeated presidential candidates Mousavi and Mehdi Karoubi, who are committed to reform, had urged supporters to take to the streets on Wednesday to protest against the government despite warnings from the security forces about "illegal gatherings."

Karoubi, who joined the protests on Wednesday, was attacked by plainclothes officers, his website Tagheer said. One of his bodyguards was hospitalized it said but gave no further details.