A homicide bomber (search) detonated a truck packed with explosives outside a Baghdad (search) police station Sunday, killing at least 39 people in the country's deadliest attack in a week. Separate attacks killed a U.S. soldier and a Marine, the U.S. military said.

The attack on the Rashad police station in the eastern neighborhood of Mashtal came during a blinding sandstorm. Security barricades prevented the bomber from reaching the station, but the huge blast destroyed two dozen cars and damaged nearby shops.

Police officials said initially that at least 22 people — most of them civilians — were killed and about 30 were injured. On Monday, the death toll rose to 39 after many of the victims burned in the bombing died overnight, said Capt. Mahir Abdul Satar.

It was the deadliest attack in Iraq (search) since a homicide bomber blew himself up July 16 near a Shiite mosque in the central city of Musayyib, igniting a fuel tanker and killing nearly 100 people.

On Monday, a homicide car bomber detonated a minibus near the Sadeer Hotel, which was once used by American contractors and has been frequently targeted by insurgents. The bomber killed five people and injured at least 18, police said.

Several hours later, a homicide bomber hit a former Saddam palace being used by the Ministry of Interior police command, killing at least two and injuring four, said to 1st Lt. Majid Zeki.

Elsewhere, gunmen killed the leader of the city council in the insurgent-riddled city of Samarra, 60 miles north of Baghdad, police said. Council chairman Taha al-Hinderah and a companion were gunned down as they walked in the Albu Rahman neighborhood Sunday evening, police Capt. Laith Mohammed said.

In Mosul, Iraq's third-largest city, insurgents emptied fuel from two tanker trucks on the Muthanna Bridge across the Tigris River and set it on fire, police said. Two people were wounded in clashes that followed.

Six policemen also were killed Sunday in scattered attacks in Baghdad and Kirkuk, officials reported. Gunmen in Kirkuk also killed an Iraqi soldier and wounded six people, police said.

The Marine was killed Saturday when a roadside bomb exploded near the desert town of Rutbah, 220 miles west of Baghdad. The U.S. command said the Marine was assigned to Regimental Combat Team-2 of the 2nd Marine Division, but the victim's name was not released.

On Sunday, one U.S. soldier was killed and two were wounded in a mortar attack near Balad north of Baghdad, the U.S. military said. The soldiers were assigned to Task Force Liberty.

As of Sunday, at least 1,777 members of the U.S. military have died since the beginning of the Iraq war in March 2003, according to an Associated Press count.

Despite the violence, Sunni Arab members of the 71-member committee drafting the new constitution signaled they were about to end their boycott, which began after last week's assassination of two of their colleagues.

The 12 Sunni Arab members of the committee announced they would meet with the Shiite chairman over breakfast Monday. Sunni committee member Saleh al-Mutlaq told The Associated Press he and his colleagues had received verbal assurances that their grievances would be addressed.

If all goes well at the breakfast meeting, "God willing we will participate tomorrow in the constitution drafting committee," he said.

The Sunnis suspended their participation to protest the assassination of Sunni member Mijbil Issa and adviser Dhamim Hussein al-Obeidi by unknown gunmen. The Sunnis demanded an international investigation into the killings, better security and a greater Sunni role in deliberations.

On Sunday, members of former Prime Minister Ayad Allawi's bloc threatened to walk out in sympathy with the Sunni demands. Committee member Adnan al-Janabi, who also is part of secular leader Allawi's eight-member bloc, criticized the way the commission dealt with the Sunnis.

"Their demands and suspension of membership should have been studied and taken in a way that reassures them and brings them to participate in the draft constitution that we want to be agreed upon by all Iraqis," he said.

Al-Janabi, who also is a spokesman for Allawi's group, said the bloc's continued participation remains in question.

"Our continuation in the committee drafting the constitution has become dependent on getting clarifications to what we have asked earlier," al-Janabi said.

The mixed makeup of the committee was deemed crucial for drafting a constitution acceptable to all of Iraq's ethnic and religious communities, a key to any political exit from the unremitting violence and the need for American troops to remain in Iraq.

If Allawi's secular group joins the Sunnis in pulling out of the process, it raises the concern that a committee already dominated by Shiite religious parties and ethnic Kurds would be left in control of drafting the charter.

Al-Janabi also expressed anger over commission chairman Sheik Humam Hammoudi's announcement that a draft would be ready within days, saying it was "a draft that we were not consulted about and I don't know how it was written or who wrote it."

Shiite member Bahaa al-Araji said no decision will be taken "without the presence of the brothers (Sunnis) unless there is a reason for the absence. Therefore, the committee will be committed to handing over the draft at the time agreed upon."

The threatened walkout by Allawi's group is the latest hurdle in the commission's goal of getting a constitution drafted and approved by the assembly Aug. 15. That charter then would be scheduled for a public referendum two months later.

Voters in only three of Iraq's 18 provinces can scuttle the constitution if they reject it by two-thirds majority in the October referendum.

Iraq has been operating under a 1959 civil status law that treated every person differently according to their sect. That law will still be in effect after the new constitution is drafted.