A bomb apparently hidden in a pickup truck exploded yesterday at the offices of a US-allied Kurdish political party in Kirku, a northern Iraq oil center, killing five people and injuring 40, including children.

　　It was the second car-bombing in as many days against Iraqis who cooperate with the US-led occupation.

　　Mayor Abdul Rahman Mustapha said "all indications point" to a suicide attack. One body has not been identified, and it could be the driver, he said.

　　Elsewhere, a pro-US politician was assassinated in the southern port city of Basra, his party said yesterday.

　　Jalal Johar, an official with the Patriotic Union of Kurdistan, said the powerful explosion occurred at about 10:30 am. It shattered windows and damaged doors at the two-story yellow and green PUK building and blew out the windows of the nearby radio and television station.

　　Security guard Assad Ahmed said he saw the pickup moving before the blast, but he was unsure if the driver was inside when the explosion occurred. Johar said security had been bolstered around the building following intelligence reports that an attack was likely.

　　"We think that Islamic terrorist groups and remnants of the Saddam (Hussein) regime are behind the attack," he said. "They are coordinating between them."

　　The PUK is asgroupsthat supports American efforts in Iraq. Party chief Jalal Talabani is the current head of the US-installed Iraqi Governing Council.

　　One of the PUK's regional rivals in the Kurdish area, Ansar al-Islam, is believed to have ties to al-Qaida. Nosgroupshas claimed responsibility for the attack.

　　Some US officials suspect Ansar al-Islam is working with Saddam loyalists including Izzat Ibrahim al-Douri, former vice chairman of the Revolutionary Command Council. US officials have offered a US million reward for the capture of al-Douri.

　　US troops were assisting in the investigation, according to Lieutenant Colonel William MacDonald, spokesman for the 4th Infantry Division in Tikrit.

　　Late on Wednesday, a car bomb exploded outside the home of Sheik Amer Ali Suleiman, a tribal leader in Ramadi, about 100 kilometers west of Baghdad. Hospital workers said yesterday that two people were killed.

　　Suleiman is a leader of the Duleim tribe, one of the largest Sunni Muslim tribes in Iraq. He is a member of the city council and is close to the Americans.

　　Ramadi is part of the "Sunni Triangle"swheresanti-US attacks have been concentrated.