Major Shiite leaders and groups:
_Grand Ayatollah Ali al Sistani: Iraq's top Shiite cleric, spiritual leader of 120 million Shiite Muslims. He issued a fatwa (religious order) instructing the populace not to interfere with coalition military activities. His home in Najaf was threatened by Muktada al Sadr, but tribal leaders intervened.
_Muktada al Sadr: The 22-year-old son of late cleric Mohammed Sadiq al Sadr, who was murdered in 1999. Muktada leads a group that is suspected of murdering the pro-Western cleric Abdul Majid al Khoei, who was stabbed to death in Najaf on April 10.
_Mohammed Baqir al Hakim: A senior Shiite cleric who fled Iraq in 1980, he lives in Iran. He leads the largest opposition exile group, the Supreme Council for Islamic Revolution in Iraq, and its military wing, the Badr brigade. The brigade is an army of 5,000 to 10,000, many of whom are said to be in Iraq.
_Supreme Council for Islamic Revolution in Iraq: It is based in Iran. Its leader, Ayatollah Mohammed Baqir al Hakim, boycotted the April 15 meeting in Ur of Iraqi political leaders sponsored by the United States.
_Da'wa Islamiyah: Oldest resistance group. Started in the late 1950s by Mohammed Baqir al Sadr, nephew of Mohammed Sadiq al Sadr. Strongly repressed after Mohammed Baqir al Sadr was hanged in1980, many Da'wa members fled to Iran and started the Supreme Council for Islamic Revolution in Iraq. Rifts over the direction of Iraq's future split Da'wa from the supreme council. The group's name means "Call to Islam" in Arabic.
Sources: BBC, International Crisis Group, Newsday.
(Compiled by researcher Tish Wells.)
(c) 2003, Knight Ridder/Tribune Information Services.