Today was the latest round of confrontation between Iran's ruling regime and the so-called "Green Wave" of opposition challenging President Mahmoud Ahmadinejad.
The Quds Day rally, an annual state-sponsored event to express support for Palestinians, became a cover for protesters looking for ways to demonstrate after their own anti-government rallies were banned.
Millions marched in the streets of Iran, according to state estimates, with two groups mixed in massive crowds. Ahmadinead supporters chanted "Death to America" and "Death to Israel," while YouTube videos showed anti-Ahmadinead protesters wearing to protest, and the Revolutionary Guards Corps vowed a swift crackdown.
By midday there were reports of limited clashes, including assaults on former president Mohamed Khatami and Mir Hossein Moussavi, whose loss in the last presidential election triggered nationwide demonstrations claiming the Adhmadinejead had rigged his reelection.
Mousavi and cleric Mehdi Karroubi, the dual figureheads of the opposition movement, had both pledged to attend the rally. Earlier today a reformist website, Mowjcamp.com, reported that the government planned to arrest them both shortly after the Quds Day demonstration.
Government supporters packed a prayer hall at Tehran University, where Ahmadinejad gave a speech blasting Israel and casting doubt on the Holocaust.
"The pretext for the creation of the Zionist regime is false…it is a lie based on an unprovable and mythical claim," he said. He added that it was Iran's "national and religious duty" to confront Israel.
For opposition supporters, Quds Day represents a turning point in how they handle demonstrations. The rally came after weeks of planning and publicity through fliers, word of mouth, and through websites and posters forwarded widely.
"This is a spark," said Mehdi Saharkhiz, a Karroubi supporter based in the U.S. whose YouTube channel featured dozens of videos purportedly from the Quds Day rallies.
Street demonstrations had largely gone quiet since July, after a severe crackdown by state security forces. More subtle protests had emerged, including the persistent nightly chants of Allahu Akbar, green graffiti on city walls and reformist slogans scribbled on paper money.
Quds Day became an opportunity for the reform movement to stage a show of force, though it remains unclear how many reformists took to the streets.
Saharkhiz, whose father was detained after working on the Karroubi campaign, says upcoming occasions like the Eid-el-Fitr, Iranian Students' Day, and the memorial for start of the Iran-Iraq War and are being eyed as prime opportunities for the protest movement.
"Today shows they can do anything…they still believe in their leaders, and people are just looking for a chance to get out," he said.