At least 55 people have died in two days of fighting between Shiite militias and U.S.-Iraq (web|news) i forces in Baghdad and the southern city of Basra, officials said Wednesday. Some 300 people were reported wounded in the clashes, which present the gravest challenge to the Iraqi government in months. The biggest toll was in Basra, the oil-rich, Shiite-majority city where an Iraqi military spokesman said 40 people were killed and 200 wounded. Col. Karim al-Zaidi did not say how many were militiamen, Iraqi soldiers or civilians caught up in the fighting. Prime Minister Nouri al-Maliki has taken personal charge of the effort to rid Basra of militias, some of whom have ties to nearby Iran. Followers of Shiite cleric Muqtada al-Sadr have been fighting U.S. and Iraqi forces in Baghdad and other cities in reaction to the Basra crackdown.

According to an Iraqi Interior Ministry official, at least 15 people were killed and 100 wounded in clashes in Baghdad's Sadr City district. The ministry official spoke on condition of anonymity because of operational security. A breakdown of who was killed was not given.

The burgeoning crisis - part of an intense power struggle among Shiite political factions - has major implications for the United States. An escalation could unravel the cease-fire which al-Sadr proclaimed last August. A resumption of fighting by his militia could kill more U.S. soldiers and threaten - at least in the short run - the security gains Washington has hailed as a sign that Iraq is on the road to recovery.

The confrontation will also test the skill and resolve of Iraq's Shiite-led government in dealing with Shiite militias, with whom the national leadership had maintained close ties.

Written By BUSHRA JUHI

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