Despite widespread blocks on mobile phones, internet sites and satellite TV stations, people in Iran have managed to tell the BBC's Persian and English interactive services what is happening in their country in their own words and pictures.
Several Iranians spoke to BBC Persian TV's live interactive programme "Your Turn" on Monday, before the channel became blocked. The programme's producers say they repeatedly invited supporters of Mahmoud Ahmadinejad to get in touch, but none has contacted them so far.
Mojgan was one of hundreds of thousands of people who attended the rally in Tehran on Monday afternoon to hear the opposition candidate, Mir-Hossein Mousavi.
She told the Farsi-language programme the numbers on Monday "were huge and the crowd kept growing". She said there was "no comparison" with the number who turned out for President Ahmadinejad's official rally the day before.
Mojgan estimated that more than one in 20 in the pro-reformist crowd were uniformed police.
Maryam, a civil servant in Tehran, went on air to say that she saw 20 busloads of people being driven into the capital on Sunday for the president's victory rally.
"But at work today, they weren't letting people leave the office to attend Mousavi's demonstration. It would have been even bigger if everyone who wanted to go had been allowed to."
Government jamming of 'phone systems and the web encouraged rumours to grow and left many Iranians feeling uncertain.
Golrokh, an Iranian student in the Netherlands told the BBC news website she had become the main news source for some of her friends in Tehran, who had "no media of their own. Nobody can trust each other because they are not connected".
Tweets revealed some of people's fears. A few hours ahead of the big rally in Tehran, Change_for_Iran tweeted: "There are now rumours of Mousavi's site being hacked and the whole rally is IRG's [Iranian Revolutionary Guards] trap. Gun placements at Azadi Square confirmed".
A few minutes later he signed off: "It's worth taking the risk, we're going."
Thousands of pro-reform supporters gathered in Tehran on Monday
A couple of callers to BBC Persian TV suggested that the size of the crowd in Tehran made the police wary of going in too hard, but they were more heavy-handed in smaller cities.
Ahmed is an unemployed graduate in Shiraz who has joined a pro-Mousavi rally every day since the results came out. He told the BBC the authorities were shipping in guards from outside the city to deal with the protests.
"The Basijis [volunteer militia] are very organised, armed with batons and sticks and they basically attack without warning".
He said the mood of the crowd had been volatile: like "Sparks of fire under the dust".
Ali, also from Shiraz, emailed the BBC Have Your Say to describe his experiences at Monday's rally in his city.
There were lots of police on motorcycles attacking people
He said tear gas was fired and then "Police on motorcycles attacked the protesters". He described taking refuge in someone's house but police broke windows to follow them in.
"They also arrested three young men and attacked another two. They started to hit them with batons ruthlessly. We could see blood running down their heads".
Ladan got in touch with BBC Persian TV: "My sister and her friends went to Molla Sadra Street in Shiraz. There were lots of guards and police on motorcycles attacking people."
Azarnoush in Shiraz tweeted: "Students are being surrounded in Shiraz University, civil police is in fight with people".
People have emailed the BBC from across Iran, in Yazd, Rasht, Esfahan and Tabriz to describe pro-Mousavi rallies.
The Iranian government views the BBC as a symbol of western corruption, so few supporters of President Ahmadinejad get in touch. Khalid Tehrani is one of them and emailed his dissatisfaction with the reformist protesters:
"This election was as fair and independent as it could be in any western country. The people who claim vote rigging should look first into the election of George W Bush in 2000 and how it was stolen from Al Gore. The West is a sore loser when it comes to the result of a democracy which is against its wishes."
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