BAGHDAD, Iraq - British Prime Minister Tony Blair held talks with Iraq's interim leader during a surprise visit to Baghdad today, and described the violence in the runup Iraqi national elections as a "battle between democracy and terror."

In a joint news conference with Prime Minister Ayad Allawi, Blair urged Iraqis to support the Jan. 30 vote.

Blair said he had just met members of Iraq's election commission, which has been targeted by insurgents. Three commission members were dragged from their car and killed by insurgents in Baghdad this week.

"I said to them that I thought they were the heroes of the new Iraq that's being created because here are people who are risking their lives every day to make sure that the people of Iraq get a chance to decide their own destiny," Blair said.

Allawi said his government was committed to holding the elections on time next month, despite calls for their postponement owing to the continuing violence.

It was Blair's first visit to Baghdad and his third to Iraq since the dictator Saddam Hussein was toppled in April 2003.

Britain has some 9,800 troops in Iraq, stationed mostly around Basra. It is the second largest contributor to the multinational force after the United States.

In ongoing violence today, a U.S. jet bombed a suspected insurgent target in central Iraq and gunmen assassinated an Iraqi nuclear scientist north of Baghdad.

Elsewhere, five American soldiers and an Iraqi civilian were wounded when the Humvee they were traveling in was hit by a car bomb near Hawija, 150 miles north of Baghdad, the U.S. military said.

The bloodshed came a day after Allawi blamed the upsurge of violence on a campaign by insurgents to foment sectarian civil war as well as derail legislative elections set for Jan. 30.

Early today, a U.S. aircraft engaged an "enemy position" with precision-guided missiles west of Baghdad, the military said.

Hamdi Al-Alosi, a doctor in a hospital in the city of Hit, said four people were killed and seven injured in the strike. He said the attack caused damage to several cars and two buildings.

In Baqouba, a city 35 miles northeast of Baghdad, unidentified assailants shot dead an Iraqi nuclear scientist as he was on his way to work, witnesses said.

Taleb Ibrahim al-Daher, a professor at Diyala University, was killed as he drove over a bridge on the Khrisan river.

And in northern Iraq, insurgents set ablaze a major pipeline used to ship oil to the Turkish port of Ceyhan, a principal export route for Iraqi oil, an official with the North Oil CO. said Tuesday.

Firefighters were on the scene, 70 miles southwest of Kirkuk, trying to extinguish the fire.

Insurgents have often targeted Iraq's oil infrastructure, repeatedly cutting exports and denying the country much-needed reconstruction money.