At least three people were killed and nine wounded in a series of car bomb attacks, including one suicidal, in Iraq's northern central province of Salahudin on Thursday, a provincial police source said. A policeman was killed and three others were wounded when a suicide bomber blew up his explosive-laden car at a police checkpoint on a main road south of the provincial capital city of Tikrit, the source told Xinhua. In another incident, provincial police chief Major General Jemaa Anad escaped unharmed from a car bomb explosion near his convoy in Tikrit, killing two civilians and wounding six others, the source said. Separately, police explosive experts carried out a controlled detonation to a car bomb found on a main road outside an army base near Tikrit, the source said. Two more car bombs were found in the city if Baiji, some 40 km north of Tikrit, and were defused by police explosive experts, the source added. Salahudin province is a Sunni dominated province, and its capital Tikrit is the hometown of former president Saddam Hussein. Iraq is witnessing its worst eruption of violence in recent years. According to the UN Assistance Mission for Iraq, almost 7, 000 Iraqis were killed and over 16,000 others injured from January to October this year.