Forty people have been killed and 80 injured in a car bomb in the Karrada shopping district of central Baghdad, local officials say.
Iraq's prime minister says he is determined to defeat the insurgents
The head of Karrada council told Iraqi TV the death toll rose overnight, and said police had thwarted a second bomb.
The attack came shortly after two mortar attacks on the central Green Zone, site of government buildings.
Earlier, at least five people were killed in attacks on two other markets in the capital.
The violence came as Prime Minister Nouri Maliki won parliamentary support for tougher security operations.
The Iraqi defence ministry said 30 insurgents were killed by Iraqi and US forces during fighting in Baghdad on Wednesday.
Officials said another 30 were captured during the clashes in the Sunni district of Haifa Street.
The troops had launched the big security operation to drive insurgents out of the area.