Iraqi police say they have killed an al-Qaida in Iraq leader in the town of Samarra, north of Baghdad.
Police say Abu Omar was shot and killed Saturday in his house after resisting authorities.
Also north of the capital, 12 bodies were discovered Saturday in a mass grave.
Iraqi authorities also announced the arrest of at least 22 Shi'ite militants Saturday, including 15 in the Shi'ite holy city of Karbala and the rest in the city of Nasariyah.
In other news, five American troops were killed Friday in two attacks in Iraq. The U.S. military says four of the soldiers died when their vehicle struck a roadside bomb in Baghdad.
Meanwhile, Iraq's largest Sunni Arab political bloc says it is negotiating with the government on a possible return to the Iraqi cabinet.
But the head of the Sunni Accordance Front, Adnan al-Dulaimi, says the bloc will not return until its demands are met. Officials with the bloc also denied press reports that it had earlier said it is ready to return to the Cabinet.
The Sunni Accordance Front withdrew from Iraq's Shi'ite majority government in August, saying it had failed to meet its demands. The demands included dealing with Shi'ite militias and reforming Iraqi security forces and detention procedures.
In other news, the U.S. military says coalition forces killed three and detained seven al-Qaida in Iraq fighters during operations near the central city of Zaganiyah.
Written statements say coalition forces detained 15 suspected terrorists Friday and today in central and northern Iraq. The detainees included a suspected "special groups" leader.
The U.S. military uses the term "special groups" to describe Shi'ite militias allegedly backed by Iran that have broken ranks with the Mahdi Army of radical Shi'ite cleric Moqtada al-Sadr.
Some information for this report was provided by AP and Reuters.