Iranian blogosphere backs Mousavi as protests mount

Websites such as Twitter and Facebook have become a focal point for young, urban Iranians opposed to President Mahmoud Ahmadinejad, who defeated Mousavi in Friday's presidential election and whose government controls the state media.

"Alert: Mousavi march still on. 5PM," read one short message, or "tweet," on Twitter.

"Good luck at the march. Don't take cars, they will be waiting for you when you return to them," read another, as tweets on the subject of the Iranian election poured onto the site every few seconds.

The Iranian government blocked SMS text messages during polling after opposition candidates used them to galvanize key young voters during the fiercely contested election campaign, and Tehran residents were still unable to send SMSs on Monday.

The BBC's Persian service was also blocked.

Social networking site Facebook, which has about 150,000 members in Iran, said on Monday it had had reports that some users in Iran were having difficulties accessing Facebook.

"This is disappointing, especially at a time when citizens are turning to the Internet as a source of information about the recent election," it said in a statement.

Unrest has rocked Tehran and other cities since the Interior Ministry released results on Saturday that showed hard-liner Ahmadinejad had defeated Mousavi by a landslide.

Mousavi has appealed to Iran's top legislative body to annul the result because of irregularities, a charge the Interior Ministry and Ahmadinejad have dismissed. The Guardian Council said it was ready to carry out a partial recount.