The government of Iran swiftly kicked the machinery of repression into high gear over the last several days in response to the largest anti-government demonstrations since 1979, when millions protested the tyrannical Shah.

One day after eight protesters were shot dead during a huge demonstration against President Ahmadinejad’s disputed re-election, the regime barred all foreign journalists from the streets of Tehran in a move that gives the security forces much more freedom to crush dissent with overwhelming force.

The regime also blocked an attempt to repeat Monday’s massive rally in support of Mir Hossein Mousavi, the former Prime Minister, who claims that he was cheated of victory last Friday by widespread vote-rigging.

Authorities have also detained 170 people since June 12, including the brother of former President Mohammad Khatami.

Supreme Leader Ali Khamenei said in an unprecedented announcement yesterday that an investigation into alleged election fraud would be carried out. Public protests are likely to continue as Iranian authorities attempt to resolve the hotly contested results. And many fear that Iranian authorities will continue to respond with attempts to stamp out the demonstrations.

In response Amnesty International has issued a call to ensure that those in power in Iran are aware that, despite their best efforts at concealing their bloody crackdown, the global community is monitoring their every move.

Help us send the vital message today to Iran’s Supreme Leader, Ayatollah Ali Khamenei, that we refuse to remain silent when authorities use violence to crush dissent and deny Iranian citizens their freedom of speech and association.

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