BAGHDAD - A string of attacks killed at least 14 people in Iraq on Sunday, officials said, in the latest violence of what has been a particularly bloody month in the country.

Iraq has been hit by a wave of bloodshed that has killed about 300 people in the last two weeks alone, raising tensions between the Sunni minority and Shiite-led government. The surge in violence has been reminiscent of the sectarian carnage that pushed Iraq to the brink of civil war in 2006 and 2007.

Sunday's deadliest attack took place in the northern city of Mosul, where a car bomb went off at a house early in the morning while a joint army-police unit was conducting door-to-door searches. The blast killed three police officers and a soldier, a provincial police officer said. Twenty people, including four civilians, were wounded.

Also in Mosul, police said militants gunned down a police officer in his car in the city center. Authorities also found a body floating in the Tigris river, shot at close range with hands bound behind the back. Mosul, 225 miles northwest of Baghdad, is a former stronghold of Sunni militants.

In northern Baghdad's Kazimiyah district, militants in a speeding car went on a shooting spree that killed three civilians and wounded another, two police officers said. A policeman was killed in another attack in the northern Waziriya neighborhood when gunmen in two cars fired on his vehicle, wounding a colleague as well.

Also, in the capital's Qahira neighborhood, militants armed with silenced pistols shot and killed a teacher, two police officers said. The motive behind the killing was not clear.

In Iraq's western province of Anbar, the birthplace of the Sunni insurgency led by al-Qaeda in Iraq, three soldiers were killed and five wounded in two roadside-bomb attacks, police and army officers said. Two medical officials confirmed the casualty figures. All officials spoke anonymously as they were not authorized to release information.

Insurgent attacks have decreased sharply in Iraq since the height of the insurgency, but recent spikes are raising fears.