At least 25 people were killed in an attack on Wednesday in Sadr City, a district east of Baghdad, a local security source told dpa.
A car bomb went off this morning near a local marketplace in the Shiite-dominated district, also injuring 44, the security source said, adding that the number of casualties is expected to rise due to the severity of the injuries.
Islamic State claimed responsibility for the assault in a statement circulated on social media. It said the extremist group had carried out a car bomb targeting a gathering of Shiite militias in Sadr City in Baghdad.
The statement could not be independently verified by dpa.
Islamic State, which controls Sunni, Arab parts of northern and western Iraq, regards Shiite Muslims as heretics.