At least 15 people were killed and 47 others injured on Thursday in attacks by a suicide bomber and a roadside bomb in the Iraqi capital of Baghdad, an interior ministry source told media.The toll could rise as ambulances and police vehicles evacuated the victims to different hospitals and medical centres in the city, Xinhua reported.Iraq has been witnessing some of the worst violence in years. Terrorism and violence have left at least 12,282 civilians dead and 23,126 others injured in 2014, making it the deadliest year since the flareup of sectarian violence in 2006-2007, according to a recent United Nations report.Many blame the current chronic instability, cycle of violence, and the emergence of extremist groups such as the Islamic State (IS) on the US, which invaded Iraq in March 2003 under the pretext of seeking to destroy weapons of mass destruction (WMD) in the country. The war led to the ouster and eventual execution of Iraqi president Saddam Hussein, but no WMD was found.