In Fallujah, police said, gunmen shot dead Sunni cleric Khalid al-Jumeili, an organizer of the western city's Sunni protest camp, in a drive-by shooting.
Sunni protest camps sprang up across the country this spring to protest what the group considers to be second-class-citizen treatment by the Shiite-led government.
A crackdown on one such camp in the north in April set off the current wave of violence, in which more than 5,500 people have been killed according to the U.N.
Medics at nearby hospitals confirmed the casualty figures for all attacks.
All officials spoke on condition of anonymity because they were not authorized to speak to media.