Dozens others were wounded in the bloody attack, said the sources.
Iraqi authorities have not yet made an official statement on the attack.
Iraq has been rocked by mass protests since early October, leaving 460 Iraqis killed and 17,000 injured, Iraq's High Commission for Human Rights said.
On Dec. 1, the Iraqi parliament accepted the resignation of Prime Minister Adel Abdul-Mahdi amid protests against corruption and poor living conditions in the country.
The premier's resignation came amid mass protests which erupted in early October against poor living conditions and government's corruption. Protesters’ demands later spiraled into calls for dissolving Abdel-Mahdi's government.
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