BAGHDAD — Gunmen assassinated a top aide of anti-American leader Muqtada al-Sadr on Friday, sharpening a Shiite power struggle that has already triggered fighting between the cleric's followers and the U.S.-backed Iraqi government.
Riyadh al-Nouri, director of Sadr's office in Najaf, was gunned down by an unknown number of assailants near his home after returning from prayer services, police and Sadrist officials said.
Sadr blamed the Americans and their Iraqi allies for the killing but called for calm — presumably to avoid a showdown at a time his Mahdi Army militia is under pressure by Iraqi and U.S.-led forces in Baghdad and southern Iraq.
Prime Minister Nouri al-Maliki, also a Shiite, condemned "this savage crime" and ordered an investigation. But many of the 5,000 people who attended Nouri's funeral later Friday in Najaf chanted "Maliki is the enemy of God" as they shouted slogans against Sadr's Shiite political rivals.
The assassination of such an influential Sadrist figure is likely to increase tension between Sadr's movement and the Shiite-led government.
Several prominent Sadrists described Nouri as a voice of moderation within the movement, arguing against an armed confrontation with the Americans and Sadr's Shiite rivals. He had also opposed a decision by the Sadrists last year to withdraw from Maliki's government.
Nouri, 41, was one of Sadr's closest aides, and Nouri's sister is married to one of Sadr's brothers.
Tension between Sadr and other Shiite parties exploded into violence last month when Maliki launched an ill-planned offensive against Shiite militias and gangs in Basra, Iraq's second-largest city.
The offensive faltered after Sadr's militia launched attacks throughout the south and in Baghdad, where militants showered the U.S.-controlled Green Zone with rockets and mortar shells, killing four Americans.
Clashes have continued in Baghdad and Basra, despite Sadr's order March 30 for his militiamen to stand down under a deal brokered in Iran.