Five mortar rounds struck the Mussayib area south of Baghdad today, killing 15 people, police and a doctor said.
The attack also wounded 23 people, the sources said.
A car bomb killed one person in Mussayib today, one of 10 such blasts to hit central Iraq that day.
Iraqi authorities are struggling to contain the worst violence to hit the country since 2008, when it was just emerging from a brutal period of sectarian killings in which tens of thousands died.
But despite measures including wide-ranging operations against militants, the violence has continued unabated.
More than 1,500 people have been killed in attacks and clashes so far this year, after upwards of 6,800 died in violence in 2013, according to AFP figures based on security and medical sources.
And all of one city west of Baghdad and part of another have been held by anti-government fighters for weeks.
It is the first time they have exercised such open control in major cities since the height of the insurgency that followed the 2003 US-led invasion.
