A mortar barrage slammed into a mainly Shiite east Baghdad neighborhood Sunday, killing 12 and wounding 31, police said.
Women and children were among the dead and wounded, and some houses in the neighborhood were damaged, according to police.
The victims were taken to Ibin al-Nafis and Sadr hospitals, police said.
Witnesses said U.S. helicopters were hovering above the attack site.
Hussein Saadon, 56, an owner of a small minibus station in the Ubaidi neighborhood, was soaked in blood after he drove four victims to the hospital.
"The attack occurred before noon. We heard sounds of four or five explosions, one after the other which hit central Ubaidi. We rushed to the place of the attack and we saw several houses which were hit. Two were badly damaged.
"We also saw a damaged car on the main street where one of the rockets landed. Two dead bodies were inside the car beside other wounded people," he said.
He said the district had been without electricity for several days and the people were suffering in the heat.
"It fills me with pain and anger to see an attack on such poor area where is no presence of police nor army bases or checkpoints," Saadon said.