TEHRAN, Iran (CNN)  -- Marching in dramatic silence, many with tape over their mouths, hundreds of thousands of Iranians kept alive public support for opposition leader Mir Hossein Moussavi Wednesday even as the government stepped up efforts to thwart daily protests calling for a new presidential election. Supporters of defeated reformist candidate Mir Hossein Moussavi line the streets of Tehran Wednesday. Large crowds gathered in Haft-e-Tir Square in central Tehran Wednesday evening for a fifth day of protests, according to witnesses. The demonstrators are demanding that officials throw out the results of the balloting Friday that kept hardline incumbent President Mahmoud Ahmadinejad in power.
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Thousands protest in Tehran in support of opposition leader Mir Hossein Moussavi
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Iranian elite military warns of legal action against social networking Web sites
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Supreme Leader Ayatollah Khamenei urges Iranians to stand behind republic
"The people of Iran are finally fed up with the lies, the temperament, the foolish actions of @placeholder," a 20-year-old Iranian man told CNN.