At around the same time, authorities say back-to-back car bombs blew up near a police station in the western neighbourhood of Sadiyah, a mainly Sunni area, killing six and wounding 15.
Another blast hit a central square in the commercial district of Karradah, killing six and wounding 14.
The force of the blast shattered the windows of Karim Sami's nearby clothing shop. Like many Iraqis in recent months, he expressed frustration with the Shiite-led government's inability to stop repeated attacks despite assurances that it is tightening security.
"We started to feel a little bit safe over the past few days because they were relatively calm, but the violence is back today," he said. "Whenever the government assures us that security is being tightened, we see attacks like these."
Car bombs also struck shopping streets in the religiously mixed western neighbourhood of Shurta, killing five people and wounding 12; the southeastern Shiite neighbourhood of Zafaraniyah, killing four and wounding 11; the southern Shiite neighbourhood of Abu Dashir, killing two and wounding nine; the mostly Shiite New Baghdad area, killing six people and wounding 17; and the largely Sunni Dora neighbourhood, killing two and wounding five, according to police.
Another car bomb exploded near an outdoor market in the Shiite village of Maamil, in the eastern suburbs of the capital, killing 3 people and wounding 41.
No one claimed immediate responsibility for the attacks, but coordinated car bombings and attacks on civilians and Iraqi security forces are a favourite tactic of the Iraqi branch of al-Qaeda. It typically does not lay claim to attacks for several days, if at all.
Iraqi officials say the lawlessness roiling neighbouring Syria, where the civil war has taken on sharp sectarian overtones similar to those that nearly tore Iraq apart, is fuelling the upsurge of violence inside Iraq. Al-Qaeda's Iraq arm and other Sunni extremist groups are fighting on the side of rebels trying to topple the regime of President Bashar Assad, which is dominated by Alawites, an offshoot of Shiite Islam.
"The recent threats of a military operation against Syria have encouraged the insurgents to wage more attacks inside Iraq. We have warned of this, but unfortunately, nobody is listening," said Ali al-Moussawi, the spokesman for Prime Minister Nouri al-Maliki.
The evening blasts added to a death toll that had been mounting throughout the day.
Authorities awoke to find four bodies with gunshot wounds to the back laying in the streets in different locations around the Iraqi capital.
Their discovery was particularly chilling because it was reminiscent of the sectarian violence that engulfed the country after the US invasion and peaked in 2006 and 2007, when corpses were commonly found dumped on the streets.
Shiite and Sunni leaders have both called for calm as the death tolls mounted in recent months, hoping to avoid a return to those dark days. But the bloodshed continues, with more than 4,000 people killed over the past five months alone. That includes 804 Iraqis killed just last month, according to United Nations figures released earlier this week.
Gunmen shot two other people dead in Baghdad's southern Dora neighbourhood, police said.
In Baghdad's southern suburbs, gunmen stormed the house of a member of a Sunni militia opposed to al-Qaeda, killing him and his wife and three children in a southern suburb of the capital, according to police.
The militia, known as the Sahwa, helped US troops fight al-Qaida at the height of the war and since been a target for hard-line insurgents who consider them traitors. Prominent Sahwa leader Wisam al-Hardan managed to escape unharmed an assassination attempt on Monday by two suicide bombers, but six of his bodyguards and a bystander were killed.
Elsewhere, a car bomb blew up early Tuesday at a restaurant in the town of Jbala just south of the capital, killing two people and wounding seven.
In the southern city of Basra, gunmen shot and killed Sunni cleric Abdul-Karim Mustafa as he was walking near the al-Taqwa mosque, said police and other officials in the city.
Hospital officials confirmed the casualty figures, and all of the officials spoke on condition of anonymity because they were not authorised to talk to the media.
- AP