A clash erupted when gunmen attacked a checkpoint manned by fighters of a government-backed Sahwa paramilitary group in Dijla town, 140 km north of the Iraqi capital Baghdad, killing a Sahwa fighter and wounding two others, Xinhua reported citing a police source.
One of the attackers was also killed and another wounded in the clash, the source said.
In another incident, gunmen detonated bomb in a house of a policeman in Mkeshiefa area, some 130 km north of Baghdad, killing a child and wounding his mother, the source added.
The policeman was not at home when the attack occurred, said a police source who did not wish to be named.
Earlier in the day, police said that at least 22 people were killed and 13 wounded in bombings and shootings across Iraq, including 10 from two families at a house south of Baghdad.
Iraq is witnessing its worst eruption of violence in recent years, which raises fears that the country is sliding back to full-blown civil conflict that peaked in 2006 and 2007, when monthly death toll sometimes exceeded 3,000.