At least seven people were killed and 64 others wounded in a series of bomb explosions in the Iraqi capital of Baghdad on Wednesday, a police source told Xinhua. The attacks occurred on Wednesday morning when up to six car bombs and two roadside bombs detonated almost simultaneously in several districts across Baghdad, the source said. A car bomb went off in Camp Sarah district near the University of Technology in east Baghdad, leaving one person killed and nine others wounded. Another car bomb ripped through a nearby busy intersection in the same district, killing one and wounding three others. And two people were killed and eight injured in a car bomb explosion in Shaab district in northeastern part of Baghdad. Another car bomb struck Baghdad's southeastern district of Zaafaraniyah, wounding nine people. A car bomb hit Shula district in northwestern Baghdad, killing a civilian and wounding 12, while a civilian was killed and six others were injured in a sixth car bomb explosion in Sadr City district in eastern the capital, the source added. A roadside bomb detonated at a busy intersection in Sadr City district, leaving a civilian killed and seven wounded. Another roadside bomb exploded in Baiyaa district in southern Baghdad and wounded 10 people, he said. The toll could rise as ambulances, police and civilian vehicles evacuated the casualties to different hospitals and medical centers in the city. Iraq is witnessing its worst violence in recent years. According to the UN Assistance Mission for Iraq, a total of 8,868 Iraqis, including 7,818 civilians and police personnel, were killed in 2013, the highest annual death toll in years