BAGHDAD, Iraq – American soldiers fired on a civilian vehicle yesterday because they feared it might hold a suicide bomber, killing at least two adults and a child northeast of the capital, American and Iraqi officials said.

The troops fired on the car because it was moving erratically outside an American base in Baqouba, 35 miles from Baghdad, an American spokesman, Major Steven Warren, said. “It was one of these regrettable, tragic incidents,” Major Warren said.

Dr. Ahmed Fouad at the city morgue and police officials gave a higher death toll, saying five people – including three children – were killed while driving home from a funeral.

Mystery continued to surround a firefight that broke out when American and Iraqi forces surrounded a house in the northern city of Mosul that was believed used by members of Al Qaeda in Iraq. Eight insurgents and four Iraqi policemen died in the assault, officials said.

Iraq’s foreign minister said tests were being done to determine if the leader of Al Qaeda in Iraq, Abu Musab al-Zarqawi, died in the raid. And an American government official confirmed that DNA from the insurgents’ bodies had been taken for testing. The official in Washington spoke on condition of anonymity because the investigation is ongoing.

However, the American ambassador to Iraq cast doubt on whether Mr. al-Zarqawi was killed. “Unfortunately, we did not get him in Mosul,” Ambassador Zalmay Khalilzad said of Iraq’s most feared terrorist.

The raid took place in a mostly Kurdish area of eastern Mosul, where attacks against American and Iraqi forces less common than in the western, mostly Sunni Arab part of the city. However, American soldiers say many insurgents live in eastern Mosul and launch attacks elsewhere.

A neighbor, Shahwan Fadhl Ali, said eight Arabs – four men, a woman and three children – had been living quietly there since last year. “They might have been Syrians or Jordanians but not Iraqis,” he said.

On Saturday, police Brigadier General Said Ahmed al-Jubouri said the raid was launched after a tip that top Al Qaeda operatives, possibly including Mr. al-Zarqawi, were in the house. In Moscow, visiting Iraqi Foreign Minister Hohshyar Zebari told Jordan’s official Petra news agency that authorities were testing DNA samples from several corpses to determine if Mr. al-Zarqawi was among them.

At the Pentagon, an Army spokesman, Lieutenant Colonel Barry Venable, said American forces “employ whatever means required” – presumably including DNA – “to identify suspected or known terrorists or insurgents.”

In Cairo, Egypt, yesterday, leaders of Iraq’s Shiites, Kurds, and Sunnis wrapped up a conference by condemning terrorism but saying the opposition had a “legitimate right” to resistance. Their statement omitted any reference to attacks on American or Iraqi forces, and delegates in Cairo said the omission was intentional. They spoke anonymously, saying they feared retribution.

The gathering organized by the Arab League also said there should be a timetable for the withdrawal of foreign forces from Iraq, a key demand of Sunni Arabs.

The differentiation between terrorism and legitimate resistance was an overture to some Sunni Arab insurgent groups, which the Iraqi government believes might be ready for talks. The plan would be to drive a wedge between those groups and extremists such as Al Qaeda.

“Though resistance is a legitimate right for all people, terrorism does not represent resistance. Therefore, we condemn terrorism and acts of violence, killing, and kidnapping targeting Iraqi citizens and humanitarian, civil, government institutions, national resources, and houses of worships,” the document said.

Also yesterday, a leading Shiite lawmaker suggested that he will pursue a federal region in southern Iraq after next month’s elections, pushing forward demands for Shiite autonomy that Sunni leaders fear could tear the country apart.

“We have major missions ahead,” Abdul-Aziz al-Hakim, who heads the largest bloc in the interim parliament, told a gathering of tribal leaders. “The central and southern regions should be achieved after the elections” set for December 15.

In other violence yesterday, gunmen killed a Sunni cleric, Khalil Ibrahim, outside his home in the mostly Shiite city of Basra, police said. The victim was a member of the Association of Muslim Scholars, a group of influential Sunni clerics that has been sharply critical of the Shiite-led government.

Four Iraqi policemen were killed and another wounded by gunmen in the town of Tarmiyah just north of Baghdad, police said.