Protesters lit fires in several streets of the capital Baghdad. They also blocked some roads there.
To the south in the holy city of Karbala, protests turned violent after a group of the demonstrators hurled projectiles at police officers.
In the southern city of Basra, the majority of main streets were closed, with protesters burning tires and setting traffic blockades around the city.
Schools, government offices and official departments in a number of southern regions were closed as protesters declared a general and comprehensive strike for all government institutions and departments in Basra.
Anti-government protests made a return in Iraq on Sunday, when a total of six Iraqi people lost their lives in renewed clashes with security forces.
The demonstrations were the latest in rallies that began in October against corruption and poor economy in Iraq.
The rallies resumed later in the month after a pause of about two weeks, but took a violent turn, with some participants vandalizing public property and opening fire on demonstrators during the mayhem.
Over 300 people have been killed in the Iraq unrest since October 1, according to the Iraqi parliament’s human rights commission.
Earlier this month, Iraqi Defense Minister Najah al-Shammari told France 24’s Arabic-language channel that a “third party” is behind shooting at the Iraqi demonstrators.