BAQUBA  - At least 23 people were killed in Iraq on Sunday, including 16 by a woman suicide bomber who blew herself up in the central city of Baquba, security officials said. The bomber detonated her explosive vest beside a police patrol near the gate of the Diyala provincial governor's headquarters and a courthouse, a security official said. Doctor Ahmed Fuad from Baquba hospital said 16 bodies had been received by the hospital's mortuary. Among those killed were eight policemen, two women and a child, he told AFP. An AFP correspondent on the scene said several police vehicles were set alight by the explosion, and nearby buildings were also damaged by the blast. The province, a stronghold of Al-Qaeda, remains one of the most dangerous regions in Iraq despite levels of violence nationwide hitting a four-year low. Iraqi and US forces have been engaged in a sustained offensive against Al-Qaeda in the province. In another attack, four people were killed when their car struck a roadside bomb on a road west of the oil hub of Kirkuk in northern Iraq, a police officer said. Two others were wounded in the blast. In a similar incident, three people including two women were killed when their car hit a roadside bomb south of Kirkuk, local police said.