Six people were killed and at least 41 were wounded in five separate bombings in central and northern Iraq early Thursday, authorities said, in the latest wave of relatively small but recurrent strikes by militants seeking to undermine the government.

More than 100 people have been killed in violence across the country since the start of the month, showing that insurgents remain a lethal force eight months after the last U.S. troops left the country.

Thursday's carnage began with a predawn attack against the house of a military officer. Militants planted four bombs around his house near the northern city of Kirkuk, according to the city's police commander Brig. Gen. Sarhad Qadir. The officer escaped unharmed, but his brother was killed and six other family members were wounded.

Hours later, a bomb in a parked car exploded near a string of restaurants, killing one and wounding 15, Qadir said. The blast seriously damaged the eateries' storefronts, scattering shattered glass and debris across the sidewalk.