Police and hospital officials say the Saturday blast struck a northern Baghdad neighborhood targeting a police checkpoint on a busy street, and that a number of policemen were among the wounded.
All officials spoke on condition of anonymity in line with regulations.
No group immediately claimed responsibility for the attack.
The number of bombings in Baghdad has decreased significantly over the past few months since the country's security forces retook nearly all the territory once held by the Islamic State group.
The extremist group claimed near-daily bombings in Baghdad over much of last year when it still held large swaths of territory in the country.
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