TEHRAN, Iran (CNN)  -- A funeral procession for a senior Iraqi Shiite leader wound through the streets of Tehran, the Iranian capital, on Thursday. Iraqi Shiite leader Abdul Aziz al-Hakim, seen in a 2007 photo, was an ally of both the U.S. and Iran. Mourners turned out to say goodbye to Abdul Aziz al-Hakim, who spent 20 years in exile in Iran before returning to Iraq after U.S.-led forces toppled Iraqi President Saddam Hussein. The funeral procession started at the Iraqi Embassy in Tehran, said Haitham al-Husseini, a senior official with al-Hakim's office and one of his advisers. Iraqi and Iranian government officials attended the procession with senior religious figures and some members of the Iraqi parliament.
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Funeral procession for Abdul Aziz al-Hakim in Tehran; another set for Baghdad
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Iraqi Shiite leader spent 20 years in exile in Iran; returned after fall of Hussein
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Al-Hakim headed Islamic Supreme Council of Iraq, helped shape Iraq's future
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He never held public office but was one of Iraq's most powerful, respected leaders
Another funeral procession is scheduled to be held Friday in @placeholder, Iraq, before the casket travels to several parts of southern Iraq with large Shiite populations.