A wave of coordinated car bombs ripped through Shiite areas of Baghdad on Tuesday, the deadliest attacks in nationwide violence that killed 50 people, as Iraq grapples with surging unrest.
The bloodshed added to concerns that Iraq is edging towards a return to the sectarian war that killed tens of thousands in 2006-2007, amid a long-running political deadlock and concerns of a spillover from the conflict in neighbouring Syria.
Eleven car bombs went off in predominantly-Shiite neighbourhoods of Baghdad, killing at least 40 people and wounding more than 100, security and medical officials said.
The blasts went off at around 6:00 pm (1500 GMT), and hit a range of civilian targets, from an ice cream shop in the central commercial district of Karrada to a popular market in the northern neighbourhood of Maamal.
Another car bomb went off near a Shiite mosque in eastern Baghdad.
And a vehicle rigged with explosives in Talbiyah, in the north, was detonated near a crowded wholesale fruit and vegetable market. It badly damaged several cars and more than a dozen shops, an AFP journalist at the scene said.
The bombings were the latest in a trend of attacks timed to coincide with people visiting cafes and other public areas during the evening.
In the past, coordinated violence has typically been confined to the morning rush-hour, when the capital is normally in gridlock.
Interior ministry spokesman Brigadier General Saad Maan, put the overall toll from the city-wide violence at nine dead, and 81 wounded in 10 attacks.
The ministry often releases casualty figures that are markedly lower than those compiled by security and medical officials. Last month it criticised what it termed "fabricated news and untrue statistics," saying that "malicious media attacks launched by some media organisations... are not less dangerous than these attacks themselves."
No group immediately claimed responsibility, but Sunni militants linked to Al-Qaeda frequently carry out coordinated attacks targeting the Shiite Muslim majority who they regard as apostates.
Ten other people were killed in attacks earlier in the day, officials said.
In the morning, gunmen entered the home of a Sunni Arab militiaman in south Baghdad and killed him, his wife, two sons and a daughter.
That came a day after two sets of attacks against the Sunni militia killed 12 people, including a coordinated assault involving two suicide bombers and a car bomb on the home of the militia's national chief in which he was wounded.
And attacks in and around Baghdad, the main northern city of Mosul and the southern port of Basra killed five people, including a policeman and a mosque imam.
From late 2006 onwards, Sunni tribal militias, known as the Sahwa, turned against their co-religionists in Al-Qaeda and sided with the US military, helping to turn the tide of Iraq's bloody insurgency.
But Sunni militants view them as traitors and frequently target them.
Attacks have killed more than 3,900 people since the start of the year, according to an AFP tally.
Iraqi officials have trumpeted wide-ranging operations targeting militants in which hundreds of alleged fighters have been captured and dozens killed, despite charges of failing to address root causes of the violence.
Officials have vowed to press on with the campaign that Prime Minister Nuri al-Maliki says has captured 800 alleged fighters and killed dozens, as well as dismantling training camps and bomb-making sites.
But the government has faced criticism for not doing more to tackle anger in the Sunni Arab community over alleged ill-treatment at the hands of Iraq's Shiite-led authorities.
Analysts and diplomats say this has given militant groups room on the ground to recruit and carry out attacks.