Iranian riot police take their positions among protesters in central Tehran Nov. 4, 2009. Police clashed with supporters of Iran's opposition leader Mirhossein Mousavi in Tehran on Wednesday when a rally marking the 30th anniversary of the storming of the U.S. embassy turned violent.

　　Iranian riot and plainclothes policemen detain a man during protests in central Tehran Nov. 4, 2009. Police clashed with supporters of Iran's opposition leader Mirhossein Mousavi in Tehran on Wednesday when a rally marking the 30th anniversary of the storming of the U.S. embassy turned violent.

　　A student waves the Iranian flag during a rally outside the former U.S. embassy in Tehran November 4, 2009.

　　An Iranian student covers her face with an Iranian flag during a rally outside the former U.S. embassy in Tehran November 4, 2009.

　　An Iranian walks past a mural outside the former U.S. embassy in Tehran November 4, 2009.