A suicide bomber killed two policemen and a civilian at a checkpoint in central Iraq on Tuesday, while attacks elsewhere killed two other people, security officials said.
The 6:10 pm (1510 GMT) bombing in the Diyala provincial capital of Baquba, north of Baghdad, also wounded seven people, Major Mohammed Karkhi said.
Police carried out a controlled explosion of a second car bomb left elsewhere in the city, Karkhi added.
Ethnically divided Diyala province is one of the few remaining strongholds of Al-Qaeda in Iraq.
In Radwaniya, west of Baghdad, an anti-Qaeda militia commander was killed by a magnetic bomb attached to his car, a defence ministry official said.
Mithaq Salman was the head of the Sahwa (Awakening) militia in the town's Dar es-Salam neighbourhood. The bomb also wounded his brother.
It was in Radwaniya that a suicide bomber killed nearly 50 Sahwa members on July 18 as they queued outside an army base to receive their pay.
Recruited among Sunni Arab tribesmen and former insurgents, the militia is credited with having turned the tide in the war against Al-Qaeda in Iraq since its inception under US military sponsorship in 2006.
It has since become a frequent target for attack by the jihadists.
In the Baghdad Shiite district of Sadr City, unidentified gunmen killed a municipal employee before taking flight, a defence ministry official said.
The violence came as the US military announced that its troop strength in Iraq had been reduced to below 50,000 as Washington prepares to declare its combat mission over at the end of the month.
The remaining troops will be deployed on an "advise and assist" mission until all US forces are due to leave the country at the end of the next year.
Copyright 2010 AFP Global Edition
