Iran's capital erupted in violence and civil disobedience for a second day Sunday, as protesters angered by what they consider rampant vote fraud in Friday's presidential election hurled rocks, set fire to storefronts and shouted anti-government slogans.
As security forces fought off the demonstrators, an assertive President Mahmoud Ahmadinejad defended his government- certified victory as the legitimate will of the people and derided the demonstrators as unimportant.
Ahmadinejad, speaking at a news conference, likened his detractors to angry soccer fans who commit a traffic violation leaving the stadium after a match. "He's going to be fined, but he's still a citizen of this country," he said.
Afterward, Ahmadinejad appeared before a massive rally in Tehran's Vali Asr square, where thousands of supporters waved red, white and green Iranian flags and banners with religious slogans.
Ahmadinejad suggested that he would not change course on major foreign and domestic issues that have made him a lightning rod for criticism from the West. He repeated his willingness to "debate" President Obama publicly at the United Nations and downplayed international concerns about Iran's nuclear research program, which Western nations believe is aimed at developing nuclear weapons and Iran says is for civilian purposes.
Ahmadinejad also rejected the possibility of an American or Israeli attack on Iran's nuclear facilities.
"Who dares to do such a thing today?" he said in response to a question from a reporter. "Who dares to even think about it? No power can even threaten Iran."
State news media quoted police officials as saying that they had detained nearly a dozen people who allegedly instigated protests and at least 160 opposition demonstrators.
Sunday's unrest drew to a close earlier than the previous day but appeared to have spread to some southern parts of the capital and drawn in more people.
At 9 p.m., supporters of moderate candidate Mir-Hossein Mousavi went on rooftops across the city and shouted into the darkness, "God is Great! Death to the dictator!" -- a dramatic gesture harking back to the days before the 1979 Islamic Revolution.
Fierce clashes erupted between supporters of Mousavi and security forces at the square near the Interior Ministry, where the election results had been certified, and around the main campus of Tehran University, a frequent scene of unrest in Iran's political and cultural battles. Plainclothes security officials rattling truncheons against the university guard railing stormed the Mousavi supporters and dispersed the crowds.
Around midnight in west Tehran's Ferdows neighborhood, residents took to the streets, chanting slogans against the president and setting trash cans on fire. In the Villa district in downtown Tehran, residents marched chanting, "We fight! We die! But we'll get our votes back."
The election commission swiftly declared Ahmadinejad the winner over Mousavi after a hotly contested race. But even before Friday's voting ended, Mousavi and another candidate, Mehdi Karroubi, had complained of massive vote-rigging.
When vote tallies were announced showing Ahmadinejad with more than 63% of the vote, rowdy riots and unrest erupted throughout the capital and in Esfahan, Tabriz, Orumieh, Rasht and Shiraz.
There were conflicting reports Sunday about whether Mousavi was under house arrest. Officials denied that he was, but Mashallah Shamsolvaezin, a confidant, said Mousavi and his wife, Zahra Rahnavard, were under house arrest and cut off from most communications.
Through a website, Mousavi called on supporters to refrain from violence and "harming themselves."
He also announced plans to formally appeal the election results through the Council of Guardians. But there seemed little likelihood that an appeal would succeed because the council is appointed by Ayatollah Ali Khamenei, Iran's top political and religious leader, who made a speech on state television strongly praising Friday's vote.
A Mousavi campaign official said his office had requested permission to hold a rally in Tehran today so he could make a speech to try to cool the passions of his supporters.
Another presidential contender, Mohsen Rezai, the sole conservative running against Ahmadinejad, said he recognized the legitimacy of the vote.
"A person who has become president through legal procedures is the president of all Iranian people," the former Revolutionary Guard commander said in a statement.
Western leaders have voiced concern about the unrest and allegations of fraud and civil liberties violations. But U.S. officials remained cautious, worried that their words could taint the opposition as American stooges.
Vice President Joe Biden said Sunday that the Obama administration would "wait and see" before drawing a conclusion about the events in Iran. Still, he expressed skepticism about the vote count.
"It sure looks like the way they're suppressing speech, the way they're suppressing crowds, the way in which people are being treated that there's some real doubt about that," he said in an interview with NBC News.
In a break with previous policies, the Obama administration has welcomed talks with Iran as a way of ending 30 years of mutual hostility and resolving an impasse over the country's nuclear program. But the reelection of Ahmadinejad -- who has created an international uproar by questioning the Holocaust and criticizing Israel -- and the weekend's televised scenes of police beating demonstrators could make such outreach less politically tenable.
There were also signs of unease about Ahmadinejad's reelection among Iran's neighbors. Some Arab countries have yet to congratulate Ahmadinejad. In Iraq, which has become a political battleground between the U.S. and Iran, some officials voiced doubt that either contender could have made much of a difference, because supreme leader Khamenei decides major foreign policy issues.
"I don't expect any change," said Sami Askari, a Shiite Muslim lawmaker and confidant of Iraqi Prime Minister Nouri Maliki. "Ahmadinejad staying as president [means] the same system, the same administration, the same government, the same attitude. [But] the system in Iran doesn't give the president such [great] power. . . . If you put anyone in the presidency, liberal or secular or whoever, he can do nothing."
Among those detained was Ahmad Zeidabadi, a dissident journalist frequently critical of Ahmadinejad.
"They put the handcuffs on and dragged him to their car and they ignored my shouting," his wife said.
Authorities also continued a crackdown on the news media, reportedly shuttering the Tehran offices of Dubai-based Al Arabiya, which is popular among Iran's restive Arab minority. Journalists have been warned their media accreditations would not protect them from security sweeps on the streets.
The semiofficial ISNA news agency quoted an official confirming that the government had blocked five pro-Mousavi websites. But after a day of blackout, the state-controlled news channel showed the clashes, minus scenes of police pummeling demonstrators.
Mostaghim is a special correspondent. Times staff writer Ned Parker in Baghdad contributed to this report.