But, reports CBS News Science and Technology Correspondent Daniel Sieberg, Tehran is having difficulty stopping citizens from using technology to report what's happening, express outrage and get people out to.
There are reports citizens in Tehran have no access to text messaging via cell phones, and opposition candidate Mir Hossein Mousavi's Web site has been down.
But Sieberg combed Twitter, Facebook, YouTube and photo-sharing site Flickr, and found that those opposing President Mahmoud Ahmadinejad refusing to be silenced.
"Against all odds," says Sieberg, "they're taking their voices to the Internet and seem to be announcing, 'The revolution will be blogged." '
"Shame on them that they think they can fool us," said one post. "Where's my vote? Really, where's my vote?" asked another.
Moments after Ahmadinejad declared victory in Iran, protestors flooded the streets of the capital.
They'd mobilized using the latest digital technology on Twitter and Facebook, Sieberg points out, while adding that there is still "no definitive way to verify the authenticity or accuracy of these reports."
"On the street level," says Trita Parsi, president of the National Iranian American Council, "people are asking themselves, 'What's going on. What does the candidate want us to do?' Well, you go to Facebook and you check what is the latest status line of your candidate, and from there they could find out what was actually taking place."
Twitter lit up with posts like this at 8:32 a.m local time Saturday: "Reports of gun shots in Fatemi Square."
Even with many Web sites down, says Sieberg, supporters of Mousavi found a way to send this tweet at 3:44 p.m. Saturday: "All Internet and mobile networks are cut. We ask everyone in Tehran to go onto their rooftops and shout 'Alaho Akbar' in protest."
"It's a tremendously skillful, talented, and Internet-savvy population in Iran," Parsi observed.
Protest videos and photos appeared on YouTube and Flickr.
Mousavi backers implored followers to declare, 'Death to dictator," on Facebook at 11:38 a.m. Sunday.
The latest tweet from Mousavi supporters called for street protests today at 4 p.m. local time, roughly 20 minutes from when Sieberg's piece aired on The Early Show.
A tweet from Monday morning, claiming to be from an Iranian student, says of Monday's planned protest, "It's worth taking the risk. We're going. I won't be able to update until I'm back. Again, thanks for your support and wish us luck."
THESE WEB PAGES HAVE THE MOST UP-TO-DATE INFO: