A car bomb explosion killed a man and wounded 40 people in the Kurdish city of Arbil and gunmen assaulted a Shia party building in Baquba, northwest of Baghdad, killing three guards, and blew up a building used by interim Prime Minister Iyad Allawi's party.

Two guards were wounded in the attack on the office of the Supreme Council for Islamic Revolution in Iraq, a moderate Shia group. One of them said the gunmen stormed the building in the mixed Sunni-Shia town at 8:30 am (0130 EDT).

In a separate attack in Baquba, armed men chased the guards from a building used by Allawi's Iraqi National Accord group and then destroyed it with explosives, police said.

The blast in Arbil, 220 miles north of Baghdad, killed a shopkeeper and wounded Mahmoud Mohammed, culture minister in the Kurdish regional government, in the head.

"I was on my way to the ministry. There was a car bomb. The blast hit my car from outside. The people who were with me were injured too," Mohammed told Reuters from his hospital bed.

"It is like any terrorist attack.

They want to end peace and democracy. The only language they know is violence. They don't want the situation to go well for the Kurds," he added.

Arbil has been relatively free of trouble since US-led forces invaded Iraq last year, though twin suicide attacks on Kurdish party offices in February killed more than 100 people.

In another attack in the north, gunmen ambushed a police patrol 30km (19 miles) south of Kirkuk, killing one policeman and wounding another, police said.

The US military said an American soldier died of his wounds overnight after an ambush in Baghdad. That brought to 623 the US combat toll in Iraq since last year's invasion.

US and Iraqi officials say they expect more violence in the run-up to the June 30 handover of power.

(Reuters, AFP)