Baghdad, Iraq ? Another day of violence in Iraq: One of two bombs mounted on bicycles destroyed a music store, a suicide car bomber attacked an Interior Ministry convoy and troops clashed with gunmen loyal to radical Shiite cleric Muqtada al-Sadr.

Later Sunday, A U.S. soldier was killed when his vehicle rolled over during a patrol in western Iraq, the military said.

Seven police commandos and two civilians died in the car bombing in Baghdad, one person was killed in the attack on the music store in Hillah, south of the capital, and eight Iraqis died in the firefight in an east Baghdad slum, according to Police Maj. Falah al-Mohamadawi. A second bicycle bomb in Musayyib, about 40 miles south of Baghdad, killed at least six and wounded 17, including the city police chief

Shiite cleric Amer al-Hussainy, a top al-Sadr aide in Baghdad, said only three gunmen were killed in the east Baghdad shootout. The five other deaths were civilians – including a woman – who were struck by stray rounds, he said.

The clash between U.S. and Iraqi forces and al-Sadr loyalists could have a negative impact on Shiite unity on whether to adopt a proposed Iraqi constitution. Al-Sadr is building opposition to the document, which will be voted on in a national referendum Oct. 15.

The U.S. soldier’s death raises to 1,914 the number of U.S. service members who have died since the Iraq war began in March 2003, according to an Associated Press count.