In the northern city of Mosul, gunmen broke into the houses of two Shabak families, killing a boy and his parents in one and a mother and daughter in the other, according to police. A bomb exploded near the house of another Shabak family, wounding six family members.
Shabaks are ethnically Turkmen and Shiite by religion. Most Shabaks were driven out of Mosul by Sunni militants during the sectarian fighting a few years ago.
Medics in nearby hospitals confirmed the casualties.