BAGHDAD, Iraq (CNN) -- A suicide bomber killed at least 50 people and wounded 60 Thursday by setting off an explosive vest in a crowd mourning the deaths of two sons of a Sunni Arab tribal leader, the Iraqi military said.
Awakening Council movement members with U.S. troops in January. The Sunni group is fighting al Qaeda in Iraq.
The bombing took place in Al-Bou Mohammed, a Sunni village dominated by the American-backed Awakening Council movement in Iraq's northeastern Diyala province.
Mourners had gathered to pay condolences to Sheikh Ibrahim Aref al-Azzawi, whose two sons were gunned down two days ago, police and Iraqi army officials said.
Both sons were members of the local Awakening Council, a movement of predominantly Sunni Muslims who have joined forces with the U.S. and Iraqi governments in battling Islamic jihadists loyal to al Qaeda in Iraq. Police said they think Thursday's bombing was aimed at intimidating members of the movement.
The sheikh is not a member of the local Awakening Council, but police suspect he and the mourners were targeted because of their sympathies toward the movement, which is cutting into what has been the insurgents' base of support.
There was no immediate claim of responsibility, but the jihadist group has been trying to scare people away from joining the movement -- which also includes some former insurgents -- and is attempting to counter its inroads.
The attack came during a bloody week in regions of Iraq where Sunni militants have had a presence. On Tuesday, bombings in Baquba and Mosul in northern Iraq, Ramadi in western Iraq, and Baghdad killed another 60 people and wounded more than 100.
In Baghdad on Thursday evening, seven Awakening movement members died in two attacks.
Saad al-Nuaimi, an Awakening Council leader in the southern Baghdad district of Dora, was killed in a drive-by shooting on a bridge, an Iraqi Interior Ministry official said. Al-Nuaimi's son, who was in the car with him, was wounded.
A roadside blast killed at least six members of an Awakening Council in the capital's northern neighborhood of Adahmiya, the official said.
A statement issued Tuesday in the name of an al Qaeda-dominated umbrella group called on Sunnis to quit the Awakening Council and government security forces and "turn all of their guns toward the crusader enemy and all of those who support them."
The U.S. military said Wednesday that a recent raid uncovered a detailed letter from an Al Qaeda in Iraq militant to the group's leader about how the insurgent network should continue to bear down against the awakening groups.
U.S. officials credit the groups with the sharp decrease in violence in the Sunni-dominated provinces of northern and western Iraq. The U.S. military estimates more than 90,000 Iraqis are taking part in the movement, receiving American paychecks ranging from about $300 to $450 a month.
• Iraq's main Sunni Arab political bloc has "agreed in principle" to return to the government, a move that would help shore up a regime beset over the last year by walkouts and quarreling, a spokesman said Thursday. Omar Abdul Sattar, spokesman for the Iraqi Accordance Front, said Prime Minister Nuri al-Maliki's military operation in the southern city of Basra targeting Shiite militants played a big role in persuading the Sunnis to change their position.
• At least two people were killed and 16 wounded in overnight clashes and airstrikes in Baghdad's Sadr City as Iraqi and U.S. troops battled Shiite militants in the capital.
• Two police were killed and six people were wounded in two roadside bombings in southwestern Baghdad, an Interior Ministry official said. The first bombing wounded two civilians. When police responded, another roadside bomb detonated at the scene, killing at least two policemen and wounding four others.
• U.S. Secretary of State Condoleezza Rice said Thursday she has no plans to meet with Iranian representatives at an Iraqi neighbors' conference she's attending next week in Kuwait. The United States, which has no diplomatic ties to Iran, accuses Tehran of arming Shiite militias in Iraq. E-mail to a friend