BAGHDAD (AP) — A suicide car bomber struck a police patrol west of Baghdad 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 U.S. 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.

Police said the blast in Ramadi, which also wounded 23 people, took place between a petrol station and an abandoned cinema in the city center. Of the eight killed, two were policemen, they said.

Initial reports from Ramadi said the blast was caused by a parked car bomb. Conflicting reports on casualties and the causes of explosions are not uncommon in Iraq in the immediate aftermath of attacks.

In Basra, Iraq's second largest city, police officials and a member of the city's security committee said the blasts there Saturday were caused by a car bomb followed by another bomb placed next to a power generator. The second blast ignited a fuel tank, according to the officials, and Ali al-Maliki of the security committee.

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.

Al-Jubouri was walking through his farmland west of the oil city of Kirkuk when the gunmen struck, killing him and wounding two of his bodyguards.

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.

Violence has dramatically dropped in Iraq since 2008, but insurgent attacks remain a daily occurrence, especially in the capital Baghdad, preventing the city from regaining a semblance of normalcy seven years after the insurgency broke out.