A suicide car bomber struck a police patrol west of Baghdad on Sunday and killed eight people, most of them civilians standing in line outside a post office to collect the monthly stipend for the country's poorest, police officials said.
The blast comes just a day after explosions tore through a market in the south, killing 43 people. Violence across Iraq has spiked in the past month as the United States moves ahead with a major drawdown of its troops set to be completed by the end of the month.
The increase in violence and the U.S. pullout have raised concerns about whether Iraqi security forces are up to the job of keeping militants from destabilizing the country further at a time of political uncertainty over who will form the next government.
Gen. Ray Odierno, the commander of U.S. forces in Iraq, vouched for the preparedness of Iraq's security forces, telling ABC's This Week on Sunday that they are ready and able to take over.
Iraq's military, he said, has "stepped up" to the challenge even as its politicians continue to squabble over the formation of a new government and new incidents of extremist violence are reported.
It is critical for Iraq, he added, to form a government after months of delay.
In other violence Sunday, a car bomb exploded near a school and a cluster of stores in the former insurgent stronghold of Fallujah west of Baghdad, killing two people and injuring four.
In northern Iraq, gunmen shot dead Abdul-Karim al-Jubouri, a local leader of a government-allied Sunni militia known as Sahwa, or Awakening Councils, that rose against al-Qaida in 2006 and 2007.
Farther north, the governor of Ninevah province, Atheel al-Nujaifi, escaped an apparent assassination attempt unhurt when a roadside bomb hit his motorcade in Mosul, the provincial capital.