The Islamic State jihadist group on Thursday claimed a suicide bombing at a police headquarters in west Baghdad, saying it was carried out by a Dutch national.
In an online statement, IS said that "Abu Abdullah al-Hollandi" carried out the attack using an explosives-rigged belt.
Security and medical officials said the Wednesday suicide bombing was preceded by a nearby car bomb and that the two attacks killed a total of 11 people and wounded 23.
But the IS statement said that information was not correct, and that there was only the suicide bombing.
IS spearheaded a jihadist offensive in June that has overrun large parts of the country, and security forces and pro-government fighters are battling to push them back.
They are now supported by US-led air strikes targeting IS in both Iraq and neighbouring Syria, while Washington and other governments have also pledged trainers to aid Iraqi forces.
Baghdad is hit by near-daily bombings and shootings that kill hundreds of people each month.
Despite being deployed at checkpoints and other positions across the city, security forces are consistently unable to prevent attacks.