A car bomb exploded at the Imam Ali mosque in Najaf during Friday prayers, killing at least 82 people, including one of Iraq 's most important Shiite clerics, Mohammad Baqir Al-Hakim. Mohammed Baqir Al-Hakim died in the bombing, his nephew told The Associated Press. "I called family in Najaf and they confirmed he was dead," said the nephew, Murthada Saeed Al-Hakim. Earlier, another relative had said the ayatollah had escaped. Dozens were injured in the blast, according to the interim government. Ahmad Chalabi, the leader of Iraqi National Congress and a governing Council member also said on Al-Jazeera, the Arab broadcaster, that Al-Hakim had been killed, quoting the cleric's brother, Abdel-Aziz Al-Hakim. Chalabi blamed U.S. forces for not keeping the region secure and said the bombing was the work of Saddam Hussein loyalists who were trying to create sectarian discord in the country. Some witnesses said, that Muqtada Al-Sadr and his followers are behind this explosion. There has been considerable unrest among the Shiite factions in Najaf, a holy city 110 miles southwest of Baghdad. The blast occurred a week after a bomb exploded outside the house another of Iraqi's most important Shiite clerics, killing three guards and injuring 10 others, including family members. **One American Soldier Killed, Four Wounded in Attack Northeast of Baghdad*** An American soldier was killed in an ambush on a convoy Friday morning and four others were injured, the military said, according to the AP. Resistance fighters fired three rocket-propelled grenades at the support convoy on a main road northeast of Baqouba, some 65 kilometers northeast of Baghdad, said Capt. Jay Miller of the 67th Armor Regiment's 3rd Battalion. Small arms fire also hit the military convoy. One of the injured troops would have to have a leg amputated, added Capt. David Nelson from the 4th Infantry Division's 2nd Brigade. Also, the deputy security chief for the Kurds in the northeastern Iraqi province of Sulaimaniya has been shot dead, an official from the Patriotic Union of Kurdistan said, accusing Islamic group Ansar al-Islam. **PHOTO CAPTION*** Iraqis dig through the rubble left after a car bomb explosion in Najaf, Friday Aug. 29, 2003. (AP Photo/David Guttenfelder)