TEHRAN (Reuters) – Iranian riot police have surrounded Tehran University to prevent the opposition from hijacking a state-organized rally on Monday to stage new demonstrations against the government, witnesses said. “There are hundreds of riot police, (they are) everywhere around Tehran University and nearby streets,” said the witness, who asked not to be named. The June 12 presidential election, which secured President Mahmoud Ahmadinejad’s re-election, sparked Iran’s worst unrest since the Islamic revolution three decades ago and exposed deep divisions in the establishment. Authorities deny allegations of vote-rigging. Iran is commemorating on Monday the killing of three students in 1953 under the former Shah. The opposition is expected to try to use the state-organized rallies to revive protests against June’s disputed presidential election. Police and elite Revolutionary Guards have warned that any “illegal” rally will be fiercely confronted. Some reformist websites called on people to gather near Tehran University campus, where the main state-rally will take place. In September, opposition demonstrators clashed with government backers and police at annual pro-Palestinian rallies. Security forces also clashed with the opposition during an anti-U.S. rally on November 4. “PLAINCLOTHES ON MOTORBIKES” On Saturday Iran banned foreign media from reporting on the Student Day rally. Journalists working for foreign media are not allowed to leave their offices to cover stories from December 7 to December 9. Another witness told Reuters that dozens of plainclothes security forces had gathered in a northern Tehran square. “Tens of plainclothes with motorbikes are at Tajrish square. More of them are joining the group,” said the witness. Opposition leader Mirhossein Mousavi criticized the clerical establishment on Sunday for suppressing students, saying the reform movement was alive in Iran despite pressure from the authorities to end it, his Kaleme website reported. Reformist website Mowjcamp said dozens of students had been arrested in Tehran and other cities in the past days. The volunteer Basij militia, alongside the Revolutionary Guards which is a key powerbase for Ahmadinejad, put down the June protests and arrested thousands. Most of have since been freed, but over 80 people have so far been sentenced to jail terms of up to 15 years and five people have been sentenced to death. The reformist opposition says more than 70 people were killed in post-election violence. Officials say the death toll was half that and included Basij militiamen. (Writing by Parisa Hafezi, Editing by David Stamp) Source: http://www.reuters.com/article/idUSTRE5B60OW20091207?feedType=RSS&feedName=worldNews&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+reuters%2FworldNews+%28News+%2F+US+%2F+International%29&utm_content=Twitter