Al Qaeda affiliate in Iraq claims responsibility for deadly Baghdad attacks From Mohammed Tawfeeq and Hamdi Alkhshali, CNN February 18, 2013 -- Updated 2146 GMT (0546 HKT) The Islamic State of Iraq releases a statement that surfaces on militant websites It says it is behind Baghdad bombings, which killed at least 21 people and wounded 125 Overall, violence in Iraq has dropped in recent years Baghdad (CNN) -- An al Qaeda affiliate in Iraq has said it was behind a string of deadly bombings that killed at least 21 people and wounded 125 others in Baghdad on Sunday. The blasts -- six car bombs and three roadside explosions -- mainly targeted outdoor markets in Shiite neighborhoods, police said. "The operation was in response to the repression of the Shiite criminal government and its policies against the Sunnis in Baghdad's neighborhoods of raids and arrests, displacement, killing, humiliation and violation of our women and livelihoods, seizing the land and the wealth of the Sunnis," the Islamic State of Iraq said in a statement, which surfaced on militant websites. "This is why the ISI mobilized Sunni men to hit them deep in a new conquest and to carry out simultaneous attacks against these impure filthy infidels," the group said. The Islamic State of Iraq is an umbrella group of al Qaeda and other Sunni extremist groups. Overall violence in Iraq has dropped significantly since the peak of sectarian violence, between 2005 and 2007. CNN's Mohammed Tawfeeq reported from Baghdad; Hamdi Alkhshali from Atlanta. CNN's Saad Abedine also contributed to this report.