A truck bomb detonated by remote control north of Baghdad killed six policemen and a member of a local group of Sunni volunteers who have turned against the insurgents, police said.
The truck was parked along the side of a road in Duluiyah, some 45 miles north of Baghdad, and exploded as police entered the vehicle to search it, said police Col. Mohammed Khalid.
In other violence, gunmen killed the head of Basra's intelligence department Saturday night in a drive-by shooting in eastern Baghdad, local police said, speaking on condition of anonymity because they were not authorized to talk to the media.
Brig. Gen. Jabar Musaid, who played a leading role in the recent government crackdown against Shiite militias in Basra, was visiting relatives in a neighborhood controlled by militiamen loyal to radical Shiite cleric Muqtada al-Sadr.
Iraqi Prime Minister Nouri al-Maliki launched the operation in Basra in late March to exert government authority in Iraq's second largest city long dominated by armed groups like al-Sadr's powerful Mahdi Army militia.
But the ongoing crackdown against Shiite extremists may have backfired when a relative of the prime minister was killed early Friday in a raid on Hindiyah, about 12 miles east of Karbala, local officials said.
Ali Abdul-Hussein, said to be a cousin of al-Maliki, was shot dead in a raid conducted by 60 U.S. soldiers supported by four helicopters and a fighter jet, said provincial police chief Raed Shakir.
Officials close to the prime minister said the killing enraged al-Maliki, who has been locked in negotiations in recent months over a long-term security agreement with the United States.
Al-Maliki demanded an explanation from the Americans, who promised an investigation into the incident, said the officials Sunday, speaking on condition of anonymity because they were not authorized to talk to the media.
Karbala Gov. Aqil al-Khuzaie said in a statement Saturday that the raid was a violation of an agreement signed with the U.S. last year that transferred Karbala to the control of Iraqi security forces.
"We are shocked to hear about the operation that has led to the killing of an innocent person," said al-Khuzaie.
Also Sunday, awakening council members opened fire on a would-be female suicide bomber, triggering her explosives belt, as she approached their headquarters 25 miles northeast of Baqouba, the Iraqi military said.
One of the members was wounded in the attack — the latest in more than 20 suicide operations carried out by women in Iraq this year.
In separate violence near Baqouba, mortars killed two women and a child on Sunday 40 miles north of the city in al-Udaim, said the Iraqi military.
Meanwhile, the U.S. military said in a statement Sunday that it detained a suspected al-Qaida in Iraq member the previous day in Udaim in an operation that destroyed two structures rigged with explosives.