The Iranian opposition dashed the regime’s hopes that its protests would gradually fade away by staging another huge demonstration against electoral fraud yesterday and calling for an even bigger show of strength today as unrest spread across the country.

The demonstrators’ defiance of bans, violent repression and official pleas for unity is driving the regime towards increasingly extreme measures to enforce President Ahmadinejad’s hotly disputed re-election last Friday.

Security forces have arrested dozens of prominent opposition figures in the past two days, detained hundreds of students in raids on universities and threatened legal action against “deviant” websites and bloggers who provoked unrest.

“Everyone is so energised and pumped up but no one knows how it will end,” one Tehran resident said. “The city is burning with equal doses of energy and rage and thugs who look like they’ve been unleashed from the city jail roam the streets wielding sticks and batons. We cannot decide whether to rejoice or despair.”

In an attempt to sway public opinion, the regime is blaming the protests on Western intelligence agencies. Last night it accused the United States — the “Great Satan” — of “intolerable” interference in Iranian affairs. The senior prosecutor in the province of Isfahan threatened demonstrators with execution, claiming that they were controlled by foreigners.

The regime could yet seek to crush the protests with a Tiananmen Square-style offensive, but the political elite is deeply split and there aresaid to be divisions even within the Republican Guard.

Tomorrow Ayatollah Ali Khamenei, the embattled Supreme Leader, is expected to call for calm and unity when he preaches in Tehran.

His words will be dissected for any sign that his support for Mr Ahmadinejad is weakening in the face of the biggest challenge to the regime’s authority in the Islamic Republic’s 30-year history. He is said to have taken a conciliatory tone in a meeting with representatives of the three defeated candidates on Tuesday night.

More than 100,000 supporters of Mir Hossein Mousavi, a former Prime Minister and Mr Ahmadinejad’s chief election rival, staged a silent rally in Tehran on the fifth consecutive day of protests yesterday, but it is likely to be dwarfed by today’s demonstration. Defying an offical ban, Mr Mousavi has called for a day of protest and mourning for the eight protesters killed at Monday’s demonstration.

“I condemn the savage acts and killing of people who only want to get their rights,” Mr Mousavi said, accusing “fraudsters and liars” of vandalising business premises to make the protesters look bad. He complained to the Supreme National Security Council about the illegal activities of plainclothes thugs using “batons, chains, iron bars or sometimes firearms”.

Mehdi Karoubi, another defeated candidate, has asked his supporters to march tomorrow, and Mohsen Rezai, Mr Ahmadinejad’s third election opponent and a staunch conservative, has threatened to challenge the official result unless the Interior Minister publishes a breakdown of the vote.

Grand Ayatollah Hossein Ali Montazeri, Iran’s most senior reformist cleric, said the rigging of last Friday’s presidential election had undermined the Islamic regime’s legitimacy and “no sound mind” would accept the results.

Parts of Tehran’s labarynthine bazaar have been closed by a strike of bazaaris. Five members of Iran’s national football team, including the captain, wore green armbands for Mr Mousavi in their match against South Korea yesterday. A fight broke out between two MPs — one hardline and the other reformist — in the national parliament.

Protests have been reported in numerous cities across Iran, including Tabriz, Shiraz, Meshad, Qom, Isfahan, Rasht, Zanjan and Zahedan. Dramatic pictures taken on mobile phones of far-flung demonstrations and police brutality are pouring into Western newsrooms, but their veracity cannot be independently confirmed.

In response the security forces and their paramilitary allies, the Basij, are reported to have raided numerous universities, hauling away students to be questioned and beaten. In the province of Khorasan Razavi alone at least 88 people have been arrested since Sunday.

The police have also arrested dozens of journalists, reformists, politicians and other opposition figures. The latest victims include Mohammed Atrianfar, a former newspaper editor close to Mr Mousavi, Saeed Laylaz, a leading political consultant, and Shiva Naza Ahari, a campaigner for human rights.

“Shiva got in touch at 1am to say that the security forces have surrounded her house and were searching it looking to arrest her. [But] she was not at her home,” a friend told The Times. “Her family were told that she should report to the Interior Ministry. Shiva was arrested from her work the next morning by the security forces.”

The regime has already moved to close down mobile telephone and text messaging systems and yesterday the Republican Guard announced that it would take action against “deviant” websites and bloggers that encouraged public unrest. It claimed they were backed by the British and American intelligence services.

‘They hit students as they slept’

As Iranian security forces raided universities across Iran, a student told The Times how five of his friends had been attacked in their dormitories after a protest outside Tehran University. One he saw again yesterday: “He was so badly injured I couldn’t recognise him.”

The student relayed his friends’ account of Sunday night’s events. “They broke the door and entered the dormitory. I saw today all the doors had been broken. They hit my friends while they were asleep. They brought them to the yard and hit them again. They arrested about 200 — five or six were killed. They took them to a military place.” The deaths have not been confirmed. According to the student, about a hundred of those held had not taken part in the protests. “About 180 were released. I think the rest were taken to Evin [prison].”

He thought that the raid had closed down the university — the site of demonstrations in the 1979 revolution — as a source of protest. “It is empty. Most of the students living in dormitories have been forced to go to their homes in the provinces. There are a lot of soldiers and plain-clothes policemen about. There will never be a demonstration there.”

His friends would not be giving up the campaign, he said. “They have motivation but they are scared. When I asked if they would continue they said they would, but hidden, wearing masks.” Ella Flaye

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