These are anti-Saddam Shiites, and they are also bitterly opposed to US Occupation.
Here is some background on the power struggle among Shiite religious leaders:
Shiite factions involved in power struggle
By Liz SlyNAJAF, Iraq - A fierce power struggle is raging through this holiest of Shiite cities, and the outcome could determine the success or failure of America's ambitious plans to reshape Iraq.
The collapse of Saddam Hussein's regime has reignited a long suppressed debate between radicals and moderates over who should lead Iraq's Shiite majority and how, transforming this once sleepy town of religious study into a hotbed of political strife.
The intrigue swirls as thickly as the desert dust through the streets. Clergymen in turbans and flowing robes huddle on corners, speaking in low voices and switching to Persian when strangers approach. At night, unexplained gunfire adds to the sense of menace. Residents are reluctant to talk; there are spies everywhere, they say, and some of the factions are armed.
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Many are preaching a far more radical brand of Islam than Sistani's, advocating revolution to achieve an Islamic republic in Iraq and sometimes calling for a jihad, or holy war, to eject U.S. troops.
The most successful of the challengers so far is Moqtada al-Sadr, son of the slain Mohammed Sadiq al-Sadr, the last Shiite leader to openly challenge Hussein's repression of the Shiite majority. His assassination in 1999 by Hussein's henchmen turned him into a hero among many Shiites.
At 30, the younger al-Sadr is still too junior in the Shiite hierarchy to count as a religious authority. He has linked up with a senior exiled Iraqi cleric, Kadhem Al Haeri, who is living in the Iranian city of Qom and who issued a fatwa earlier this month appointing al-Sadr his deputy "in all affairs."
The fatwa effectively gives al-Sadr more religious authority than Sistani, said al-Sadr's spokesman, Sheikh Adnan al-Shahmani, because Haeri has achieved "a higher level of religious knowledge" than Sistani. He is also more radical.
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