At least 21 people have been killed when explosives packed into three shopping carts ripped through a crowded market in the Iraqi capital.
An interior ministry official said 107 people were wounded in the attack, which happened at 6.45pm when the area was crowded with shoppers.
Also on Thursday, an American contractor with USAID was killed and another US citizen wounded in a bomb attack as their armoured vehicle was leaving a Baghdad university, the US embassy and witnesses said.
In other violence in central and northern Iraq on Thursday, car bombs and improvised explosives killed four people, two of them security personnel, and wounded 14 others, four of them policemen.
Violence has fallen dramatically in Iraq since its peak in 2006 and 2007, but attacks against government officials and institutions have risen in recent months, as Iraqi leaders bicker over key security posts left vacant since a March 2010 general election.
The surge in the number of attacks comes with only months to go before US forces are due to complete a pullout under the terms of a 2008 security agreement.