Thirty-eight people have died and 105 were wounded in central Baghdad on Monday morning following a double suicide attack.
The twin bombings took place in Tayyaran square during rush hour.
The number of dead and injured had risen from initial reports of 26 dead and about 90 injured.
"Two suicide bombers blew themselves up in Al Tayyaran square in central Baghdad," said Gen Saad Maan, spokesman for the Joint Operations Command, which includes the army and the police.
Tayyaran Square is a bustling centre of commerce and a place where day labourers gather in the early morning waiting for jobs.
It has been the site of deadly attacks in the past. Ambulances gathered at the site of the bombing and security forces had been sent in large numbers.
There was no immediate claim of responsibility, but most such attacks in Iraq are the work of ISIL.
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On Saturday, a suicide bomb attack near a security checkpoint killed at least five people in northern Baghdad. There was no immediate claim of responsibility.
The bombings come as Iraq gears up for elections in May.
Iraqi prime minister Haider Al Abadi has said he will stand for re-election in the parliamentary polls as the head of a new coalition.
Mr Al Abadi's newly created Victory Alliance will compete against the State of Law bloc of Nouri Al Maliki, his predecessor and a key rival who is now vice president.
Both are members of the Shiite Dawa party.
Mr Al Abadi was little known when he became premier three years ago, after Mr Al Maliki ceded power to him in August 2014 amid ISIL's sweeping attack.
Mr Al Abadi has rebuilt the armed forces and taken back disputed areas in the north from the Kurds, dashing their hopes for independence.
He has also succeeded in convincing the Hashed Al Shaabi, a Shiite-dominated paramilitary force that helped in the fight against ISIL, to join his Victory Alliance.
The Hashed, or Popular Mobilisation Units, are now looking to become a key political player in Iraq after proving to be a formidable force on the battlefield.
In November, ISIL claimed an attack by suicide bombers on a market on the outskirts of Baghdad that killed 11 people.