Eight people, including a mother and three of her children, were killed in a bomb attack in northern Baghdad.
The attack on Sunday targeted a police patrol in the predominantly Sunni neighbourhood of Adhamiyah in the Iraqi capital, a police source told Al Jazeera.
Four policemen were also among the dead, after a sticky bomb placed under their vehicle exploded.
The bloodshed began earlier on Sunday, when at least 13 people died in a suicide bombing in the city of Ramadi. The explosives were set off at a checkpoint staffed by the army and local police.
According to news agency AFP, the suicide bomber detonated a vehicle packed with explosives on Hauz bridge, which connects north and south Ramadi. The city originally had five bridges across the Euphrates River, but two are for the exclusive use of security forces and two are damaged beyond repair.
In the northern city of Mosul, seven soldiers were killed by gunmen who attacked an army base.
The violence occurred a month before parliamentary elections, which are due to take place on April 30 and would be the first national vote since 2010.