As the Iranian government warns protesters to stay off Tehran's streets, there are reports that those who support reformist presidential candidate Mir Hossein Mousavi still plan to rally.
The Guardian points to this message on Mousavi's Facebook page:
The CRUCIAL Demonstration on Saturday 16:00 in Tehran and all around the world, please spread this message around
16:00 is right about now (7:30 a.m. ET) in Tehran.
The BBC also reports that it was told by Mousavi's wife that the protest would be happening.
As the Associated Press notes:
Rallying could spark a bloody crackdown on Mousavi's supporters, or greatly weaken the government by forcing it back away from its threat of violence.
We'll pass on more as today's news develops. Click your "refresh" button to make sure you're seeing our latest additions. You can also click on "Hourly News Summary" at the top of this page to hear NPR News' latest newscast. NPR.org's coverage of the disputed Iranian election is collected here.
Update at 3 p.m. ET. The White House just released a statement from President Barack Obama, who calls on Iran's government to "stop all violent and unjust actions against its own people." Here's the text:
"The Iranian government must understand that the world is watching. We mourn each and every innocent life that is lost. We call on the Iranian government to stop all violent and unjust actions against its own people. The universal rights to assembly and free speech must be respected, and the United States stands with all who seek to exercise those rights.
"As I said in Cairo, suppressing ideas never succeeds in making them go away. The Iranian people will ultimately judge the actions of their own government. If the Iranian government seeks the respect of the international community, it must respect the dignity of its own people and govern through consent, not coercion.
"Martin Luther King once said -- "The arc of the moral universe is long, but it bends toward justice." I believe that. The international community believes that. And right now, we are bearing witness to the Iranian peoples' belief in that truth, and we will continue to bear witness."
Update at 2:45 p.m. ET. Two pictures from Tehran today, courtesy of AFP/Getty Images:
Update at 11:10 a.m. ET: Night is approaching in Iran -- which, judging from previous experience, could bring more clashes between militia forces, students and protesters. We'll check in again later on the news from Tehran.
Update at 10:45 a.m. ET: Among the blogs posting photos said to be from Tehran today is Tazahorate Ma.
Update at 10:33 a.m. ET. Reports of injuries:
The AP writes that "eyewitnesses described fierce clashes near Revolution Square in central Tehran after some 3,000 protesters chanted 'Death to the dictator!' and 'Death to dictatorship!' Police responded with tear gas and water cannons.
"The witnesses told The Associated Press that between 50 and 60 protesters were seriously beaten by police and pro-government militia and taken to Imam Khomeini hospital in central Tehran. People could be seen dragging away comrades bloodied by baton strikes."
Update at 10:25 a.m. ET. Video:
The independent Tehran Bureau has a live tweetstream here. It's pointing here to what is thought to be among the first videos from today's events in Tehran.
Update at 10:05 a.m. ET. The BBC posts this dispatch from an unnamed correspondent, whose identity is presumably being protected for his or her safety:
"I'm in the centre of Tehran close to Enghelab Square, where the demonstration was supposed to have been held. But there's a huge security presence here, thousands of men from every possible service: police, Revolutionary Guard, military police, the riot police in full riot gear, and the much-feared basiji - religious paramilitaries who see themselves as the shock troops of the Islamic revolution.
"It's impossible for any groups of people to get through these to Enghelab Square and hold their demonstration."
Update at 9:39 a.m. ET: Al Jazeera English is webcasting its coverage here. Its correspondent is raising the possibility that the bombing reported to have happened near the shrine of Ayatollah Khomeini was the work of the government, which might be trying to pin blame on the protesters.
Update at 9:29 a.m. ET. Tear gas and water cannons:
According to the AP, "witnesses say police are using tear and water cannons to disperse thousands of protesters rallying in Tehran to demand a new presidential election."
Update at 9:23 a.m. ET. Reports of a blast near Khomeini's shrine:
Reuters writes that "a bomb exploded in Tehran on Saturday, killing one person and wounding two, Iran's semi-official Fars news agency reported. It said the blast occurred near the shrine of Iran's
revolutionary founder, Ayatollah Ruhollah Khomeini."
NPR News has not independently confirmed the report.
Update at 9 a.m. ET: The BBC's Jon Leyne sums up the current situation:
"Very tense and very confused. We don't have direct, immediate reports from the scene because of course we're not allowed to go there."
Update at 8:45 a.m. ET: CNN says it has been told that police blocked several thousand protesters from getting to one rally site.
Update at 8:40 a.m. ET: The AP says firetrucks have been placed around likely protest sites -- resumably so that water hoses could be aimed at protesters. If you'd like to follow a rolling Twitter feed of all the tweets tagged #Iranelection, Weekend Edition's Soapbox blog has embedded one here.
Update at 7:50 a.m. ET: CNN is saying it's been told by a source that armed police are at the likely rally sites. NPR News has not independently confirmed that report.
If you want to see what's being written on Twitter, try this link.