BAGHDAD — American-backed Sunni militias who have fought Sunni extremists to a standstill in some of Iraq’s bloodiest battlegrounds are being hit with a wave of assassinations and bomb attacks, threatening a fragile linchpin of the military’s strategy to pacify the nation.

At least 100 predominantly Sunni militiamen, known as Awakening Council members or Concerned Local Citizens, have been killed in the past month, mostly around Baghdad and the provincial capital of Baquba, urban areas with mixed Sunni and Shiite populations, according to Interior Minister Jawad al-Bolani. At least six of the victims were senior Awakening leaders, Iraqi officials said.

Violence is also shaking up the Awakening movement, many of whose members are former insurgents, in its birthplace in the Sunni heartland of Anbar Province. On Sunday, a teenage suicide bomber exploded at a gathering of Awakening leaders, killing Hadi Hussein al-Issawi, a midlevel sheik, and three other tribesmen.

Born nearly two years ago in Iraq’s western deserts, the Awakening movement has grown to an 80,000-member nationwide force, four-fifths of whose members are Sunnis. American military officials credit that force, along with the surge in United States troops, the Mahdi Army’s self-imposed cease-fire and an increase in Iraqi security forces, for a precipitous drop in civilian and military fatalities since July.

But the recent onslaught is jeopardizing that relative security and raising the prospect that the groups’ members might disperse, with many rejoining the insurgency, American officials said.

“There’s a recognition that sustained attacks cannot continue,” said a United States official who was not authorized to speak publicly. “We’ve got to break that.” The official said that American military and intelligence officials were taking the threat to the Awakening movement “very seriously.”

American and Iraqi officials blame Al Qaeda in Mesopotamia for most of the killings, which spiked after the Dec. 29 release of an audio recording in which Osama bin Laden called the volunteer tribesmen “traitors” and “infidels.” While the organization is overwhelmingly Iraqi and Sunni, American military officials say it has foreign leadership, though its links with Mr. bin Laden himself are unclear.

Officials say that Al Qaeda in Mesopotamia has a two-pronged strategy: directing strikes against Awakening members to intimidate and punish them for cooperating with the Americans, and infiltrating the groups to glean intelligence and discredit the movement in the eyes of an already wary Shiite-led government. “Al Qaeda is trying to assassinate all the Awakening members that support the government, but I believe that criminal militias are also doing this,” Mr. Bolani said during a recent interview in Taji.

Both Sunni and Shiite officials in Baghdad blame two government-linked Shiite paramilitary forces for some of the attacks: the Mahdi Army and the Badr Organization. Sunni officials charge that militia leaders are involved, while Shiite officials believe that the attackers are renegade members of the groups. Both militias have close ties to Iran and have been implicated in death-squad operations against Sunni Arabs, although the Mahdi militia’s leaders have publicly told their members to abide by a cease-fire.

Citizen guardsmen and Iraqi intelligence officials say they have also captured Iranians with hit lists and orders to attack Awakening members. American military officials say they suspect that Iran’s paramilitary force, Al Quds, is directing the Shiite militias’ attacks against the Awakening movement. But other than finding Iranian-made weapons, which are sometimes used by Shiite militia fighters, American military officials offered no evidence that Iranians were participating in direct attacks. “Right now, the Concerned Local Citizens groups are being heavily targeted by Al Qaeda,” said Brig. Gen. Mark McDonald, who is working with the volunteers. “They’re also being targeted by some Shiite extremist groups.”

Killings of guardsmen are mounting even as Awakening members are becoming increasingly frustrated with the Iraqi government, which has yet to fulfill its promise to integrate 20 percent of the volunteers into the Ministries of Interior and Defense and give nonsecurity jobs to the rest — a process that American officials say could take until the end of the year.

“If I give you a gun and tell you to stand at a checkpoint but I don’t give you support, how long will you stay?” asked Khadum Abu Aya, one of the Awakening leaders in Adhamiya, a neighborhood in northwest Baghdad that was once dominated by Sunni insurgents.

Officials in Baghdad who support the movement worry that if attacks on the tribal forces continue without faster progress by the Iraqi government, Awakening members could begin to fall away, harden into antigovernment militias or even rejoin the Sunni Arab insurgency.

Source:http://www.nytimes.com/2008/01/24/world/middleeast/24sunni.html?_r=1&hp&oref=slogin