On Saturday, in Tarmiyah, north of Baghdad, militants blew up four houses belonging to police and soldiers while people slept inside. Four people were killed, including a soldier, and 15 others injured.
Southeast of the capital, a roadside bomb in a market killed one person and wounded eight, while a magnetic "sticky bomb" on a car killed an electricity ministry employee in Baghdad itself.
A roadside bomb also killed a civilian in Baiji, north of Baghdad, while militants attacked a checkpoint near the town, leaving two gunmen and a soldier dead.
After the attack, authorities announced a curfew in the area.
Gunmen also attacked a local council member's convoy near Baquba, north of Baghdad, killing one of his guards and wounding two.
Iraq is witnessing its worst violence since 2008, when the country was just emerging from a brutal sectarian conflict that killed tens of thousands of people.
There are persistent fears that the country is slipping back towards an all-out conflict.
Militants, including those linked to al-Qaeda, frequently carry out attacks against Iraqi security forces and other government employees.
The latest violence brings the death toll to more than 740 people in September and more than 4,550 this year, according to security and medical sources.
RA/HH