"I am deeply troubled by the violence that I've been seeing on television," Obama said in Washington. "I can't state definitively one way or another what happened with respect to the election. But what I can say is that there appears to be a sense on the part of people who were so hopeful and so engaged and so committed to democracy who now feel betrayed."
Khamenei for years has tried to put his own religious ultra-conservative faction in charge of all branches of government. He marginalized not only the nation's secularists but reformist and pragmatist leaders who were pillars of the Islamic revolution, risking a backlash by barring huge swaths of people from political power.
There were few signs that the unrest would let up. Across the crowd, people passed information about another gathering Tuesday in Vali Asr Square, in central Tehran. Mousavi supporters also called for a general strike Tuesday. "I am fed up with the rigging of votes," said Nargess Hassanpour, 24, an architect. "I had never voted until last Friday. I am here and I march toward Azadi Square as far as I can reach, and let come what may."
From adjacent office buildings, supporters waved and cheered, holding up pictures of Mousavi, as passing cars, taxis and minibus drivers honked in support.
The pro-government Basiji militiamen stood along the sidelines, appearing stunned by the magnitude of the crowd. They have become the scourge of Mousavi supporters after fighting demonstrators for two nights and storming Tehran University the previous night, injuring dozens of students.
University activists alleged that the Basiji killed five students as they stormed the campus to quell a demonstration. The school's chancellor confirmed the attack but did not mention the deaths.
By 5 p.m., a flood of people surged from west to east toward the huge expanse of Freedom Square, nearly filling the entire roadway as well as the surrounding green space, with more demonstrators pouring in from all directions. They held up their fingers in the "V" signs that have become popular.
"Rockets, tanks, Basiji no longer have any effect on us!" they chanted, updating a popular slogan from the 1979 Islamic Revolution.
"If I died today it would be perfect," said Hossein, 60, a retired schoolteacher, walking through crowd with the help of a cane. "The nation of Iran has woken up."
Khamenei's decision to heed the call for a vote review followed a late-night meeting with Mousavi, who is a cousin, in what observers described as a tactical measure to buy time in the hopes that Mousavi and his supporters will cool down.
"The way people came out today after he announced this, nobody believes it's in good faith, because they have lost trust in him," said Mousavi. .
