Security forces opened fire on protesters in the southern Iraqi city of Nassiriya late on Saturday, killing at least three people, police and medical sources said.
Protesters had gathered on three key bridges in the city, and security forces used live ammunition and tear gas canisters to disperse them, the sources said.
More than 50 others were wounded, mainly by live bullets and tear gas canisters, in clashes in the city, they added.
At least 330 people have been killed since the start of mass unrest in Baghdad and southern Iraq in early October, the largest demonstrations since the fall of Saddam Hussein in 2003.