A series of car bombs exploded in Shiite areas of Baghdad Tuesday, killing at least nine people and injuring more than 60, an interior ministry official said.
Two of the bombs exploded within half an hour of each other in the capital's Sadr City Shiite bastion, killing six people and wounding 32, the official said.
The first bomb ripped through a group of workers at around 6:45 am (0345 GMT) while the second exploded outside a bakery. Among the wounded were two women and a child.
A third car bomb exploded in Shula, a northwestern district of the capital, killing two people and wounding 16, while a fourth killed one person and wounded 13 in the northern neighbourhood of Al-Hurriya, the official said.
The bombings are the latest in a spate of attacks against Shiites, which have risen since US forces completed their withdrawal from Iraq on December 18.
Though violence in Iraq is down markedly from its peak during 2006 and 2007, attacks are still common, and more than 200 people have been killed since the US drawdown.
The pullout coincided with a political crisis in Iraq, pitting the Shiite-led government against the main Sunni-backed bloc which accuses Prime Minister Nuri al-Maliki of centralising power.
Reflecting the ongoing tensions, the Honein jihadist forum posted a message on Monday vowing further attacks against Iraqi Shiites.
"The violent attacks against the Rawafid (the name used for Shiites by Sunni extremists) will continue," Al-Qaeda front group the Islamic State of Iraq said in a statement, while claiming responsibility for attacks on Shiite pilgrims over the past month.
"The lions of the Islamic State of Iraq (will not cease their operations)... as long as the Safavid government continues its war. We will spill rivers of their blood as reciprocity."
The jihadists often invoke Iran's Safavid past, referring to the Shiite dynasty that ruled Persia between the 16th and 18th centuries, and conquered part of Iraq, when denouncing the Baghdad government, which they say is controlled by Tehran.