Militant groups who were allegedly behind the attacks were attempting to stir up sectarian violence, Xinhua reported, but no group has claimed responsibility for the attacks.
The deadliest attack took place at a market and parking lot in Hillah city, Xinhua reported.
The bomb killed five people and injured 27 others, police said.
Car bombs were also detonated in Basra, Kut, Sawyrah and Diwaniyah, as well as other cities.
The attacks come after another car bomb exploded Saturday near a market in Samarra, Iraq, killing 24 people and injuring 34 others, officials said.
The explosion happened Saturday as a large number of people, mostly women and children, were shopping to prepare for the Muslim holiday of Eid Al-Adh, the Kuwaiti news agency KUNA reported.
A security official said the victims were transported to Samarra General Hospital.
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