U.S. and Iraqi troops backed by heavy artillery and helicopters killed 15 insurgents in fighting Sunday that began in palm groves and ended in dusty streets of a city north of Baghdad (search) as violence surged throughout the country.

Also Sunday, insurgents assassinated a former government official in Baghdad and gunned down five people in a series of attacks in the northern Iraqi oil city, Kirkuk (search). A U.S. soldier was killed by a roadside bomb on Saturday near Beiji.

The carnage coincided with the start of delegate selection in Baghdad for a three-day national conference considered a key step in moving the country away from its totalitarian past and toward a democratic future.

The conference, which will select 80 of 100 interim National Assembly members, is scheduled for this week. Organizers refused to confirm the location -- and even the exact date -- of the conference, fearing terrorist attacks.

Militants angry at the presence of foreign forces here and bent on derailing efforts to restore order to Iraq after more than two decades of Saddam Hussein's (search) rule have waged a 15-month insurgency, marked by car bombings, assassinations and kidnappings.

A raid Sunday against insurgents in Buhriz, a former Saddam stronghold about 35 miles north of Baghdad, turned into a five-hour battle between militants and U.S. and Iraqi forces.

Military spokesman Maj. Neal O'Brien said the clash was ignited when U.S. and Iraqi National Guard troops conducted a sweep of palm groves believed to be a staging area for anti-coalition attacks.

Insurgents using small arms attacked the Iraqi forces, who chased the attackers into the town's southern neighborhoods, the U.S. military said. Iraqi fighters later fired mortars indiscriminately, and the U.S. responded with an artillery barrage.

Associated Press Television News recorded several loud explosions, apparently from artillery and mortar fire, booming through Buhriz and bullets ricocheting off building and shop walls. Residents ran for cover as an Apache helicopter hovered overhead.

Local Iraqi fighters, most clad in black clothing and ski masks, roamed the streets carrying rifles and rocket propelled grenade launchers.

The military said 15 insurgents were killed.

Qayser Hameed, an emergency worker at the nearby Baqouba General Hospital, said two dead Iraqis -- a police officer and a civilian -- and six injured civilians were brought to hospital.

It was unclear if the two killed were in addition to those the military said had been killed. Yasir Ahmed Ismail, the slain police officer, died in his house when a mortar hit nearby, said police Lt. Mohammed Adel.

The battle followed a U.S. soldier's death Saturday in a roadside bomb attack near Beiji, about 90 miles south of the northern city of Mosul, the military said.

The soldier, escorting a fuel convoy, suffered serious wounds and died later Saturday. Another soldier was injured.

In Baghdad's al-Dora suburb, gunmen killed Brig. Khaled Dawoud, the former head of Nahyia district in southern Iraq during Saddam's rule, and his son in a drive-by shooting Sunday, police Lt. Mustafa Abdullah al-Dulaimi said.

Also Sunday, Pakistan said two of its citizens working for a Kuwaiti firm had disappeared in Iraq. "They are missing. It is not known yet if they have been kidnapped. No group has contacted us for kidnapping them or made any demand," said Masood Khan, a spokesman for Pakistan's Foreign Ministry.

An important Sunni religious group on Sunday condemned the separate abductions of an Egyptian diplomat and seven foreign truck drivers last week.

Meanwhile, an important Sunni religious group on Sunday condemned the separate abductions of an Egyptian diplomat and seven foreign truck drivers last week.

"If a hostage is unrelated to occupation forces, their abductors should free them if they are to respect Islamic religious principles," said Dr. Mohammed Bashar al-Faidhi, spokesman for the Association of Muslim Scholars, an Iraqi Sunni Muslim group with close ties to insurgents.

Militants said they snatched Mohammed Mamdouh Helmi Qutb, the third-ranking diplomat at the Egyptian mission here, to deter Egypt from sending security assistance to Iraq's interim government.

Another group has threatened to behead an Egyptian, three Indians and three Kenyans if their employer did not stop doing business here and compensate victims of coalition attacks in Fallujah, their countries did not pull their citizens out of Iraq and the United States and Kuwait did not free Iraqi prisoners. Al-Faidhi also said that attacking police was prohibited, because they were responsible for "providing people with security.

Kidnappings and other rampant violence have threatened Iraq's efforts to rebuild the country after the war and years of sanctions and establish democracy.

As part of an important first step on the road to democracy, about 540 people gathered under tight security Sunday at former Baghdad country club to choose 26 delegates to the upcoming Iraqi National Conference.

Iraq must have "real democracy," stressed Abdullah Mansour, sent from Baghdad's western Abu Ghraib area to vote. "I know everyone has a different idea of what it should be, but while it needs to be nurtured slowly it also has to be accountable."

In other violence Sunday, gunmen killed two officers traveling to work at Mahmoudiya police station, about 25 miles south of Baghdad, police Lt. Alla Hussein said.

Police officer Luay Abdullah was also among five killed in a brazen shooting spree across the northern city of Kirkuk.

Gunmen in a passing car killed Abdullah early Sunday while he waited for a ride home after his shift guarding a pipeline, said Kirkuk police Col. Sarhad Qadir.

Assailants also sprayed gunfire at a Kurdish family's house in a predominantly Arab area in south Kirkuk, killing a woman and two of her sons and injuring a daughter, Qadir said.

Shirwan Jilal, a fighter with the pro-U.S. Patriotic Union of Kurdistan party, was also killed in a drive-by shooting late Saturday while walking home.

Qadir blamed the attacks on "a gang of criminals related to the previous regime who want to create feuds between Arabs and Kurds."