Violence erupted in Tehran yesterday as tens of thousands took to the streets to attack the regime on a day that was supposed to be dedicated to condemning America.

The regime marked the 30th anniversary of the storming of the US Embassy with an official rally outside the former diplomatic compound — but elsewhere, security forces fought running battles with protesters who packed the streets of the capital in defiance of regime warnings.

Opposition videos showed riot police and Basij militiamen clubbing men and women and charging into crowds of demonstrators, leaving many with bloody head wounds.

The protests were smaller than in the immediate aftermath of June’s disputed presidential election, but were matched by demonstrations in several other Iranian cities. Opposition figures said that they were large enough to make the point: despite five months of brutal suppression, the opposition had not been crushed.

“What’s important is not that we got people out, but they came from across the social spectrum — old, young, male, female, religious and irreligious.

“This is a people’s movement that the system can’t destroy,” said one activist. “We have again sent a message to [President] Ahmadinejad and the [Supreme] Leader that society has not forgotten what they’ve done,” said another. “They have beaten, raped, tortured and threatened the people but we still showed up.”

Observers said that a huge force of Revolutionary Guards, riot police and volunteer Basij militiamen spread across Tehran before dawn, closed metro stations, and shut the mobile telephone system.

They charged the crowds with batons, teargas and electric prods, and squads of motorbikes. They made dozens of arrests. They fired shots in the air, and opposition websites posted video footage of demonstrators fleeing down streets and nursing wounds. Cars that supported the protesters by sounding their horns were attacked, and police helicopters hovered.

Basiji surrounded the Academy of Arts to prevent Mir Hossein Mousavi, the former Prime Minister defeated by Mr Ahmadinejad in June, from joining the demonstrations. Mehdi Karroubi, another defeated presidential candidate, was attacked, then bundled away by supporters when he appeared in central Haft-e-Tir Square.

Security forces sought to keep students inside campuses. At Tehran University they were reportedly confronted by more than 2,000 students and professors, with girls standing in front of the boys to protect them.

Witnesses said that the demonstrators chanted “Death to dictators” and “No fear, no fear. We are all together.” Violence was met with violence, and there were several reports of them beating police or Basiji. Opposition videos showed them tearing down posters of Ayatollah Khamenei, the Supreme Leader.

The state-controlled media broadcast little of this. It focused on the official anti-American rally outside the old US Embassy compound.

Iranian journalists are permitted to cover only official events, while most foreign journalists have been barred from Iran.

The storming of the US Embassy, after which 52 Americans were held hostage for 444 days, has resulted in three decades of hostility between Iran and the US. President Obama marked yesterday’s anniversary by challenging the hardline regime to end the era of suspicion, mistrust and confrontation. “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.

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