The blasts, which wounded scores more, are part of a months-long surge of attacks that is reviving fears of a return to the widespread sectarian bloodshed that pushed the country to the brink of civil war after the 2003 US-led invasion.
Suicide attacks, car bombings and other violence have killed more than 3,000 people since April, including more than 500 since the start of July, according to an Associated Press count.
Eight police officers said a total of 12 parked car bombs hit markets and parking lots in predominantly Shiite neighborhoods of Baghdad within one hour.
They say the deadliest was in the eastern Shiite neighborhood of Sadr City, where two separate explosions killed nine civilians and wounded 33 others.
Ambulances rushed to the scene where rescuers and police were removing the charred and twisted remains of the car bombs from the bloodstained pavement. The force of the two explosions lightly damaged nearby houses and shops.
In the southwestern neighborhood of Bayaa, three civilians were killed and 15 wounded in another car bomb explosion. In western Baghdad in the neighborhood of Shurta, two other people were killed and 14 wounded.
In the southern Abu Disheer area, four civilians were killed and 17 wounded. Another car bomb struck in the northwestern Tobchi district, killing three and wounding ten others.
Five more people were killed and 44 others wounded in the southwestern Risala neighborhood, the northern Shaab neighborhood and in the town of Mahmoudiya, about 30kilometers south of Baghdad.
