BAGHDAD, Iraq (CNN)  -- A leader of the Sons of Iraq anti-al Qaeda group was killed Saturday when a bomb attached to his vehicle exploded, an Iraqi Interior Ministry official said.

U.S. soldiers arrive on the scene of a suicide bombing Saturday in Kirkuk, Iraq.

Two civilians were wounded in the explosion in southern Baghdad's Dora district, the official said.

The Sons of Iraq, or Awakening Councils, are mainly composed of former Sunni insurgents who turned against al Qaeda in Iraq. They are considered a major factor in the reduction of violence in Iraq over the past two years and are frequently targeted by al Qaeda.

In other violence across Iraq on Saturday:

â€¢ At least 19 people were wounded in a bombing at a coffee shop in Baquba, a security official in Diyala province said. The coffee shop is frequented by U.S.-backed anti-al Qaeda fighters. The explosion wounded 17 group members and two civilians, the official said. Baquba is about 35 miles north of Baghdad.

â€¢ At least seven people, including three Iraqi Army soldiers, were wounded when a roadside bomb struck an army patrol in northern Baghdad's Qahaira neighborhood, the Interior Ministry official said.

â€¢ At least one police officer was killed and nine people -- seven police and two civilians -- were wounded when a suicide bomber detonated an explosive vest near a police academy in Kirkuk, according to a police official. Kirkuk is located in oil-rich northern Iraq, about 150 miles north of Baghdad.

CNN's Jomana Karadsheh and Yousif Bassil contributed to this report.
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question: What killed the leader of Sons of Iraq?, answer: bomb attached to his vehicle exploded, | question: Where was the bomber from?, answer: Iraq | question: What are the "Sons of Iraq"?, answer: anti-al Qaeda group | question: Who was the roadside bomb aimed to kill?, answer: Iraqi Interior Ministry official | question: What kind of store did the al Qaeda members go to?, answer: a coffee shop | question: Number of people wounded by Kirkuk suicide bomber?, answer: nine | question: Where was the bomb attached?, answer: vehicle | question: Number of people wounded by coffee shop bombing?, answer: At least 19 | question: Who was killed by the bomb?, answer: A leader of the Sons of Iraq anti-al Qaeda group | question: Where was there a suicide bombing that killed a police officer?, answer: Kirkuk, Iraq. | question: What killed a leader of Sons of Iraq, answer: bomb attached to his vehicle