Iran’s opposition leader appealed for restraint as his supporters regrouped after Saturday’s bloody confrontations with the security forces.

Mir Hossein Mousavi, defeated in a presidential election that his followers say was rigged, issued a statement mourning those killed, denouncing the “mass arrests” and insisting: “Protesting against lies and fraud is your right.”

Bursts of gunfire were reported as Tehranis took to their rooftops to shout protests under cover of darkness, but for the first time in a week there were no big demonstrations. That was partly because Tehran’s streets were flooded with police and Basiji militiamen, and partly because the protesters were still reeling from the previous day’s brutality.

“The mood is sombre, tense and shocked,” one Tehran resident told The Times. “I really don’t think people expected what happened yesterday. It’s done serious damage to people’s psyche. It was an absolute war zone.”

Another said: “The capital city is quiet. It feels like a bad movie, as though everyone is pretending that yesterday did not happen.”

According to the official figures, ten people died and 100 were injured as the security forces used batons, tear gas, water cannon and bullets to break up the protests. Many Iranians believe that the real figures are double or treble that.

Chilling clips of injured protesters, including one showing a young woman apparently dying of head wounds on a Tehran street, appeared on Western websites. Some ambulances and hospitals were ordered to surrender protesters who sought treatment. Tehran residents gave shelter and first aid to fleeing demonstrators.

“At the end of the day we had to walk over the wounded and some dead people,” Afasar, an office worker, told The Times. “I couldn’t believe this was Tehran, my home. I can’t believe they did this to us. I will never forget those images and I will never forgive.”

Mogjan, a middle-aged housewife, ran into an alley to escape the security forces and begged a woman to let her into her building. “It looked like a war zone, with wounded and bleeding people all over,” she said. “From the apartment we could see them beating and shooting at the people. I never thought an Iranian could be so cruel and brutal against an Iranian. How could they do it? The inhumanity was impossible to understand.”

David Miliband, the Foreign Secretary, deplored the “continuing violence against those seeking to exercise their right of expression”. President Obama, facing Republican criticism for not denouncing the violence more forcefully, urged the regime to “stop all violent and unjust actions against their own people”. Austria and Italy instructed their Tehran embassies to help the wounded.

However, the regime continued to arrest opponents including, most notably, the eldest daughter of Ali Akbar Hashemi Rafsanjani, the former President, who backed Mr Mousavi in the hotly disputed presidential election.

Analysts suggested that Faezah Hashemi was being held “hostage” to stop Mr Rafsanjani making trouble. He heads the Assembly of Experts, which has the power to depose Ayatollah Ali Khamenei, the Supreme Leader, who backs President Ahmadinejad.

Reporters Without Borders said that 24 Iranian journalists and bloggers had been jailed, adding: “The Islamic Republic now ranks alongside China as the world’s biggest prison for journalists.” Students were said to be deleting all incriminating e-mails from their computers.

The regime is using the statecontrolled media to portray the demonstrators as pawns of foreign powers bent on destroying the Islamic Republic, calling them “terrorists” and “rioters”. It claims that they burnt a mosque on Saturday, and that a suicide bomber blew himself up at the tomb of Ayatollah Ruhollah Khomeini, the founder of the Republic; claims that are impossible to verify.

“The police will confront all gatherings and unrest with all its strength,” Azizullah Rajabzadeh, the commander of Tehran police, said.

The protests are far from over, however. As darkness fell last night tens of thousands of Tehranis opened their windows or went on to their rooftops to chant “Allahu Akbar” (God is great) and “Death to the dictator” in protest at the election results. Each night more people join in.

Hossein, an engineer who had been severely beaten, said that he had no regrets about protesting. “It has given me back my voice. The amazing thing is that I didn’t know I had one, but now they can never force me to shut up again. Our Government has spilled our blood, that will never change, and we will never stop.”

“It’s going to continue to escalate,” an Iranian analyst said. “The genie is out of the bottle, and no one can put it back in. There’s a genuine and deep anger.”

Mr Mousavi said that he was defending revolutionary values against the “deception and lies” of Iran’s rulers. He rejected an offer by the Guardian Council to recount 10 per cent of the votes and repeated his demand for a new election. He urged supporters to amass evidence of electoral fraud and state violence.

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