The bombings occurred simultaneously at three marketplaces, Xinhua reported.
Sadr City is predominately a Shiite neighborhood and a stronghold for Mahdi Army militia, loyal to radical cleric Moqtada Sadr, the state-run Chinese news service noted.
CNN reported the bombings came in the wake of a series of attacks and bombings targeting Iraq's Shiite population.
Attacks Thursday and Friday in Baghdad and Iraq's Diyala province resulted in the deaths of nearly 160 people and injuries to 275, CNN said.
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