Baghdad, Iraq ? U.S. officials are negotiating with Sunni Arab leaders to pull insurgents into Iraq’s political process, a senior U.S. official said Wednesday. An American-Iraqi offensive, meanwhile, killed at least 10 militants, including four blown apart by their own car bomb.

The U.S. official’s statement to reporters came after a Sunni Arab politician and a senior Shiite leader told The Associated Press they were talking with some groups in the insurgency, thought to include up to 20,000 fighters in their ranks.

“Some insurgents are irredeemable and have to be dealt with in a purely military way, and there are some who are looking to enter the political process under some conditions,” the official told a Baghdad briefing, given on condition of anonymity.

At least 20 Iraqi army soldiers are feared kidnapped in western Iraq near the Syrian border, an Iraqi army official said Wednesday. They went missing Tuesday after leaving an Iraqi army base in two minibuses from Akashat, a remote village southwest of Qaim, said Capt. Ahmed Hamid.

Four U.S. soldiers died in separate attacks north of Baghdad, the military said Wednesday. One died in a roadside bombing Wednesday near Adwar. Two more died in a Tuesday attack on their Tikrit base, while a fourth was killed in a bomb attack just north of the capital.

At least 1,682 U.S. military members have died since the war began in 2003, according to an Associated Press count.

Fighters killed at least nine more Iraqis, including two government officials, in drive-by shootings and a car bomb as part of the ongoing bloodshed that has left almost 900 people dead in the six weeks since Iraq’s new Shiite and Kurdish dominated government was announced April 28.

Even as political efforts to unite Iraq appeared to gain steam, the president, Jalal Talabani, made comments that could anger Sunnis. He publicly praised Shiite and Kurdish militias, including the Shiite Badr Brigade that Sunni Arabs accuse of terrorizing and killing members of their once dominant community.

A woman shouts during a protest in Iraq's southern city of Basra. More than 200 Iraqis demanded from the local government on Wednesday housing for their families and to release nine of the detainees who were arrested by police two days ago.

And top Sunni leaders, sensing their crucial role in the future of Iraq’s government, demanded a greater say in drafting of the constitution and threatened to boycott the process if they didn’t get it.

U.S. authorities have negotiated with key Sunni leaders, who are in turn talking with insurgents and trying to persuade them to lay down their arms, the senior U.S. official told reporters. The official did not name the Sunni leaders engaged in dialogue.

The official did not give his name so as not to undercut the new government’s authority.

Sunnis form the backbone of Iraq’s raging two-year insurgency.

The official suggested further measures to calm tensions, including absorbing existing militia groups like the Badr Brigade and the Kurdish Peshmerga into Iraq’s own security forces.

At a conference marking the second anniversary of the Badr brigade’s claimed transformation to a political group, Talabani offered public praise.

“You and your (Kurdish) brothers are the heroes of liberating Iraq,” he said. “You, my brothers, march on without paying attention to the enemies’ claims because you and the (Kurdish militia) are faithful sons of this country.”

Talabani’s remarks came despite accusations by Sunni leaders that the militia – formed in 1982 to launch cross-border attacks from Iran against Saddam Hussein’s forces – has killed members of the minority. The Sunni leaders have demanded it be disarmed and complained it provides intelligence and support for some Shiite-dominated special security units.

Sunni Arab criticism of Talabani’s remarks was swift.

Abdul-Salam al-Qubeisi, spokesman of the influential Association of Muslim Scholars, said the president was following “U.S. policies to prolong the struggle in Iraq and turn it into an Iraq-Iraq conflict.”