The car bomb exploded at about 7:45 pm (1645 GMT) near a football field in Hilla, 95 kilometres (60 miles) south of Baghdad, killing eight people and wounding 32, police Second Lieutenant Ali Jassem and doctor Saad al-Khafaji of Hilla hospital said.
And a roadside bomb killed four people and wounded seven in Baquba, 60 kilometres (37.5 miles) north of Baghdad, according to a police colonel and doctor Ahmed Ibrahim of Baquba General Hospital.
The latest violence brings the number of people killed in attacks in Iraq since June 13 to at least 171 -- more than were killed in attacks in all of May, according to official figures.
On June 13, 72 people were killed and over 250 wounded in attacks across Iraq, which were later claimed by Al-Qaeda`s front group, the Islamic State of Iraq (ISI).
Three days later, two car bombs targeted pilgrims in Baghdad, killing 32 people and wounding dozens on the peak day of commemorations for the 799 death of Imam Musa Kadhim, the seventh of 12 revered Shiite imams.
On June 18, a suicide bomber targeted Shiite mourners in Baquba, killing 22 people and wounding dozens more, while shootings and a bombing killed six people in Iraq on June 19,
And on Friday, attacks killed at least 12 people and wounded dozens more.
While violence in Iraq has declined dramatically since its peak in 2006-2007, attacks remain common. A total of 132 Iraqis were killed in violence in May, according to official figures.(*)