A truck bomb detonated by remote control killed seven people north of Baghdad on Sunday, including 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 75 kilometers 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 20 kilometers 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 US soldiers supported by four helicopters and a fighter jet, provincial police chief, Raed Shakir, said. 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 US 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. On Sunday, awakening council members opened fire on a would-be female suicide bomber, triggering her explosives belt, as she approached their headquarters 40 kilometers 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 70 kilometers north of the city in Udaim, according to the Iraqi military. Also Sunday, the US military said in a statement 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. The military also said Sunday that Iraqi security forces arrested three suspected al-Qaida in Iraq members and four suspected "special groups criminals" in operations around central Iraq on June 24-26. The military uses the latter term for Shiite militiamen refusing to follow a cease-fire order by al-Sadr.