At least 40 people have been killed after four bombs ripped through Shiite areas of Baghdad in the worst violence the capital has seen in months, Iraqi officials have said.
An American civilian contractor also died in a separate attack.
The violence underscored the fragile nature of the security gains in Iraq at a time when American forces are preparing to withdraw by the end of this year.
The first three bombs went off in quick succession in an area of south-western Baghdad shortly after 7pm local time on Thursday.
One targeted a Shiite mosque, another exploded just outside a popular market, while the third went off inside the market where people were doing their evening shopping ahead of the Muslim weekend, said Iraqi police officials.
The officials said 34 people died and 82 others were injured in the three blasts. An official from Baghdad's Yarmouk hospital confirmed the casualty figures.
An Iraqi resident, Jabir Ali, said he was about 200 yards away when one of the bombs went off near a barber shop where his cousin works.
"I saw many people killed and injured. I went to see my cousin. The glass at his shop was broken and he was injured in his head, chest and hand by the glass," said Mr Ali, who drove his cousin to the hospital.
About an hour later, a parked car bomb targeting a police patrol killed six people, including one policeman and five bystanders in a different area of south-western Baghdad, said hospital officials.
There was no immediate claim of responsibility, but Sunni extremists such as al Qaida in Iraq generally tend to target Shiite mosques and neighbourhoods and Iraqi security forces.