Unknown gunmen firing Kalashnikovs and PK machineguns ambushed a police patrol Thursday in north Iraq, killing two policemen and three civilians and wounding six more, a top police officer said. The gunmen ambushed the police patrol about 40 kilometres (24 miles) south of the northern city of Kirkuk, killing two policemen and three civilians and wounding three policemen and three civilians, Brigadier General Sarhad Qader said. The gunmen fired from three cars, Qader said, adding that they battled police for about 30 minutes before managing to flee. The Al-Qaeda and Ansar al-Sunna militant groups are active in the area, Qader said. Ethnically divided and oil-rich Kirkuk province lies at the centre of a tract of territory which Kurdish leaders want to incorporate in their autonomous region in the north despite the opposition of many of the province\'s Arab and Turkmen residents, and of Iraqi Prime Minister Nuri al-Maliki. Violence in Iraq has fallen sharply from a peak of 2006 and 2007, but attacks still continue across the country. In March 112 Iraqis were killed in violence.