Many of the victims were Iranian pilgrims, CNN reported.
A roadside bomb exploded about 12 miles north of the capital Baghdad, killing at least five Shiite pilgrims on a minibus traveling to a shrine. About a dozen other passengers were injured.
Most of the dead and injured were Iranian pilgrims, police said.
Five people were killed and seven wounded in four separate attacks in and around Mosul, about 235 miles north of Baghdad.
Two shootings and two bombings targeted houses and shops related to the Shabak sect, who were mostly affected by the incidents.
The government has blamed the attacks on Sunni insurgents with ties to al-Qaida.