A bomb car went off outside a police station in the northern city of Kirkuk, killing five and wounding over 25. Kirkuk is split by ethnic tensions. For decades, Saddam drove Kurds out of the city and replaced them with Sunni Arabs. He did this because Kirkuk is the main city in the northern oil region. Since the fall of Saddam's government, the expelled Kurds have been returning and demanding, and sometimes acting, to get their homes and land back. This has made recruiting for Sunni Arab resistance groups easier, and Kirkuk has been the scene of attacks, mostly on Iraqi police.
In the south, there was a rare attack on an oil pipeline. Attacks in the north, by Sunni Arabs fearful of Kurdish retribution, have been controlled by setting up a security organization of Iraqis to guard the oil facilities. There is no such security operation in the south.
The spectacular suicide bombing attacks get the most attention, but the violence that is doing the most damage are the assassinations of political and religious leaders. The killers are apparently former members of Saddams secret police, seeking to terrorize the new Iraqi government into accepting the return of Sunni Arabs to power. While these seems absurd to Americans, in the Arab world, such terror tactics are seen as practical and, alas, all too common. The antidote for such attacks is massive roundups of suspects and the use of torture and summary execution of captives to find out who the killers are. These tactics are no longer allowed. Western styles of police work are used instead, and teaching Iraqi police how to use databases, non-lethal interrogation and other Western policing techniques is an ongoing process.