He was 45 but his white hair and lined face made him look 60. Tears filled his eyes as he watched marchers protesting over the presidential election results file past yesterday, chanting “Give us back our Iran!” and holding up two fingers for victory.He had fought on the side of Ayatollah Khomeini to overthrow the Shah in 1979, he said, but felt betrayed when the cleric returned from exile and imposed strict Islamic rule. He was looking at his younger self. “It’s just like the revolution,” he said, pulling a black cap down over his eyes, declining to give his name because he was an economist in a government ministry.The hundreds of thousands of men, women and children who marched in sweltering heat nine miles down Enghelab Street in the heart of Tehran hope they can force another turning point in Iranian history. They want change and the annulment of the election they believe rigged by President Mahmoud Ahmadinejad.

After the hordes mustered by President Ahmadinejad in the capital yesterday, this show of defiance and strength was the opposition’s response. One policeman said between 1.5 million and two million people had turned out, but the numbers were all but impossible to guess.

“Since the day the (Khomeini) revolution went the wrong way, we have been waiting for someone to stand up and say something so people could follow him,” the tearful civil servant said, moving off as the feared secret police edged in to eavesdrop. “That somebody is Mousavi.”

And then Mir Hossein Mousavi appeared in public for the first time since the election on Friday he claims to have won. Emerging from the midst of the vast crowd, he clambered onto the roof of a car to speak and acknowledge the massed support stretching far into the distance. “God willing, we will take back our rights,” he shouted.

Few could hear him above the crowd but it didn’t matter, it was enough that he was there. He cuts an unlikely hero of the opposition. He was close to Ayatollah Khomeini, and as Prime Minister from 1981 to 1989 is remembered for successfully managing the economy but also for presiding over a cultural crackdown. He admits that he has not one iota of charisma.

His lacklustre campaign took off only a little more than a week before last week’s election when Mr Ahmadinejad held up a photo of Zahra Rahnavat, Mr Mousavi’s wife, a renowned scholar and artist, during a televised presidential debate and insulted her by claiming she had fake academic credentials.

The wealthy of northern Tehran flocked to his cause, wearing the green that symbolised his campaign and crowding the streets late into the night in canvassing that turned into all-night partying.

They were entranced by his wife’s feistiness when she stood up to Mr Ahmadinejad, and loved that the couple travelled the campaign trail holding hands publicly, something never before seen in Iran.

Now they and their supporters held one of the capital’s main boulevards. Glamorous young women, their hijabs pushed back to reveal the blonde streaks that are fashionable in Tehran, and their obligatory overcoats so tight and short they looked like fashion statements, walked beside middle-aged men with the rough skin and work clothes of labourers.

Spontaneous cheers went up. “Death to the Taleban in Kabul and Tehran!” shouted another group in unison. “All Tehran is here,” said Mona, 24, an employee of a software company dressed conservatively in a navy blue hijab demurely on her forehead and a billowing black robe. But she wore black adidas trainers eneath this traditional garb. “To escape,” she laughed.

“My friends told me not to come, I might get beaten or killed,” she said. “I had to come. They stole my vote. The election was cheating – everyone in Tehran knows that Mousavi won and they made it the wrong way round.”

Her words revealed the bravery of the marchers. Not only were they defying the Government – the Ministry of Interior not only refused to give the march a permit, but said if the demonstration went ahead as planned “the consequences of such behaviour will be felt by Mousavi” – but they were risking beatings, arrest or worse.

Swarms of the motorcycle-mounted riot police and members of the Basiji, the dreaded militia loyal to Ahmadinejad, have been roaming the capital, many mobilised from outlying provinces. Armed with heavy truncheons and stun guns, they beat the young men and women who have been protesting by gathering on corners to chant slogans or setting fire to rubbish in the green metal bins that are ubiquitous on Tehran’s streets.

They attacked the University of Tehran campus in the early hours of yesterday, ransacking dorm rooms, beating students, and smashing computers.

The marchers went on and on. A government source said the Ministry of Interior yesterday authorized the use of live ammunition. Far worse scenes of the revolution could be replayed.

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