JIM LEHRER: Major new protests erupted in Iran today in the wake of last month's disputed presidential election. Police and militiamen squared off with thousands of protesters. Lindsey Hilsum of Independent Television News begins our lead story coverage.
LINDSEY HILSUM: Violence on the streets of Tehran today. Opposition supporters still protesting. The Basij militia armed with what looked like handguns. No journalists allowed, but images are still emerging.
Tear gas fired at the crowds who gathered after Friday prayers. Giving the sermon, the most powerful cleric to support the opposition. "Iran is in crisis," said Hashemi Rafsanjani. "Those arrested for protesting about last month's election should be freed."
AKBAR HASHEMI RAFSANJANI, Former President of Iran (through translator): It's not necessary that in the current situation we keep some people under these allegations in jail. Let them go and take care of their families.
LINDSEY HILSUM: In the front row, leading opposition figures. But the man protesters say won the election, Mir Hossein Mousavi, was almost lost in the crowd and not shown on state television. Mr. Rafsanjani acknowledged their belief that the elections were rigged.
AKBAR HASHEMI RAFSANJANI (through translator): Doubt has been created in people's minds. We consider doubt to be the worst calamity.
LINDSEY HILSUM: The crowd started to shout pro-Mousavi slogans. He hushed them, saying he was speaking on their behalf. Mr. Rafsanjani was directly challenging Iran's supreme leader for endorsing what he sees as a flawed election.
Opposition supporters wearing green wristbands gathered near the mosque and along the streets. Normally, the government encourages people to attend Friday prayers, so they couldn't ban people from trying to get there. Some carried pictures of their defeated candidate, Mir Hossein Mousavi.
They chanted as they walked, shouting, "Freedom, freedom, independence." Instead of the government cry -- "death to America" -- they shouted, "Death to Russia," which is seen as a major backer of President Ahmadinejad.
But it wasn't tolerated. The Basij militia fired tear gas into the crowd. A few protesters managed to film on their mobile phones as they fled. A leading opposition figure, Mehdi Karroubi, was reportedly beaten up, and at least 15 people were arrested.
State television broadcast a few shots of the crowd as the riot police arrived on motorbikes. They said Hashemi Rafsanjani had called for unity, but today's protests show that the government has failed to crush the opposition.