At least 136 people have been killed and 600 wounded in twin car bombings targeting government buildings in central Baghdad.
The powerful blasts went off less than a minute apart in car parks near the headquarters of the Baghdad provincial administration and the Ministry of Justice building.
The death toll was the highest caused by bombings in Iraq for more than two years.
Iraqi leaders said the attacks aimed to disrupt political progress in the months leading up to January's crucial elections.
While violence has dropped dramatically in the country since the height of the sectarian tensions, the latest bombings underscored the precarious nature of the security gains and the insurgency's abilities to still pull off devastating attacks in the centre of what is supposed to be one of Baghdad's most secure areas.
The street where the blasts occurred had just been reopened to vehicle traffic a few months ago when blast walls were repositioned to allow traffic closer to the government buildings. Such changes were touted by Iraq's prime minister as a sign that safety was returning to the city.
President Jalal Talabani said: "The perpetrators of these treacherous and despicable acts are no longer hiding their objective but to the contrary, they publicly declare that they are targeting the state ... and aiming at blocking the political process, halting it and destroying what we have achieved in the last six years."
There have been no claims of responsibility so far, but massive car bombs have been the hallmark of the Sunni insurgents seeking to overthrow the country's Shiite-dominated government.
Black smoke billowed from the frantic scene, as emergency service vehicles sped to the area. Even civilian cars were being commandeered to transport the wounded to hospitals.
At least 25 staff members of the Baghdad Provincial Council, which runs the city, were killed in the bombing, said council member Mohammed al-Rubaiey.
