A suicide bomber blew himself up on Tuesday amid tribal leaders and army officers killing at least 33 people, including two journalists, and injuring 46 others outside the town hall in Abu Ghraib, on Baghdad's western edge, security officials said.
Major-General Qassim Moussawi said the attack took place as the dignitaries, including army officers, toured a market in the Abu Ghraib district.
Journalists, police and soldiers were among those killed, the source said.
A source at Yarmouk hospital, the main hospital in western Baghdad, said it had received the body of a journalist working for al-Baghdadiya, an independent television station. Another journalist with al-Iraqiya state television was wounded, he said.
Today's carnage came after a suicide bomber on a bicycle killed 28 people and injured 56 outside a Baghdad police academy on Sunday, the bloodiest attack in weeks.
The White House on Tuesday dismissed suggestions the two bloody attacks were a reaction to President Barack Obama's decision to pull out most combat troops by August next year.
White House spokesman Robert Gibbs said security challenges remained in Iraq, but said U.S. agreements with the Baghdad government would not have been made if they were likely to plunge Iraq back into "danger."
Gibbs was asked whether the two attacks were an encouragement to those plotting attacks or emboldened those bent on violence.
"No," said Gibbs, adding that he was not aware of any specific intelligence about such a scenario.
"But I know that the president and the team remain committed to ensuring that Iraq is a stable and secure country going forward and that we'll continue to continually evaluate that."
While violence has dropped sharply in Iraq since the height of the sectarian and insurgent bloodshed unleashed by the U.S.-led invasion in 2003, insurgents continue to stage regular attacks, especially in the volatile northern city of Mosul.
Improved security has encouraged Iraqis to cautiously resume a more normal life in Baghdad, but violence continues there, too.
The United States is planning to reduce its troop force of around 140,000 ahead of a full withdrawal date by the end of 2011, raising questions about whether local security forces will be ready to prevent Iraq sliding back into large-scale bloodshed.