Security forces and pro-government militiamen clamped down in the Iranian capital to prevent protests Tuesday as the country’s police chief warned his forces would take a tough line if the opposition tries to take to the street.Plainclothes Basiji militiamen hit passers-by with batons on a crowded main Tehran street to ensure they wouldn’t gather, according to video from the site posted on line. A young woman in a headscarf can be seen arguing with the Basijis, who shove her.Regular police forces were out in large numbers in parts of central Tehran, causing large traffic jams, but witnesses around the city speaking to The Associated Press did not report that any protests came together. There was no immediate report of arrests in the day’s clampdown.Some opposition activists had called for demonstrations Tuesday to mark the passage of 30 days since the killing of Neda Agha Soltan, a 27-year-old woman shot to death during a Tehran demonstration on June 20. Her dying moments on the street were caught on video and she was elevated to a symbol of the mass protest movement that erupted after Iran’s disputed June 12 presidential election.The protest call was also issued to coincide with the anniversary of nationwide protests that brought liberal Prime Minister Mohammad Mossadegh to office in 1950.Last month’s presidential election sparked massive protests by hundreds of thousands in support of opposition leader Mir Hossein Mousavi, after he claimed that official results were fra… >>>