A wave of 16 bombings ripped across Baghdad Thursday, killing at least 69 people in the worst violence in Iraq for months.

The apparently co-ordinated attacks struck days after the last American forces left the country and in the midst of a major government crisis between Shia and Sunni politicians that has sent sectarian tensions soaring.

The bombings may be linked more to the U.S. withdrawal than the political crisis, but all together, the developments heighten fears of a new round of Shia-Sunni sectarian bloodshed like the one a few years back that pushed Iraq to the brink of civil war.

There was no immediate claim of responsibility. But the bombings bore all the hallmarks of al-Qaeda's Sunni insurgents. Most appeared to hit Shia neighbourhoods, although some Sunni areas were also targeted.

In all, 11 neighbourhoods were hit by either car bombs, roadside blasts or sticky bombs attached to cars. There was at least one suicide bombing and the blasts went off over several hours.

Co-ordinated campaigns such as this generally take weeks to plan, and could have been timed to coincide with the end of the American military presence in Iraq, possibly to undercut U.S. claims that they are leaving behind a stable and safe Iraq.

Al-Qaeda has long sought to sow chaos and provoke the type of Shia militant counterattacks that defined Iraq's insurgency. At least 14 blasts went off in the morning and there were two more in the evening.

Suicide bomber targets government agency

The deadliest attack was in the Karrada neighborhood, where a suicide bomber driving an explosives-laden vehicle blew himself up outside the office of a government agency fighting corruption. Two police officers at the scene said the bomber was driving an ambulance and told guards that he needed to get to a nearby hospital. After the guards let him through, he drove to the building where he blew himself up, the officers said.

Sirens wailed as ambulances rushed to the scene and a large plume of smoke rose over the area. The blast left a crater about five metres wide in front of the five-storey building, which was singed and blackened.

"I was sleeping in my bed when the explosion happened, said 12-year-old Hussain Abbas, who was standing nearby in his pajamas. "I jumped from my bed and rushed to my mom's lap. I told her I did not to go to school today. I'm terrified."

At least 25 people were killed and 62 injured in that attack, officials said. They spoke on condition of anonymity because they were not authorized to speak to the media.

Figures gathered from Iraqi health and police officials put the death toll across the city at at least 69, and at least 200 injured, including the two evening blasts in western Baghdad neighborhoods that killed nine people and injured 21.

In Washington, the White House condemned the bombings and said attempts to derail progress in Iraq will fail. Press secretary Jay Carney said the attacks serve no agenda "other than murder and hatred."

Stability questions

Iraqis are already used to horrific levels of violence, but many wondered when they would be able to enjoy some measure of security and stability after years of chaos.

"My baby was sleeping in her bed. Shards of glass have fallen on our heads. Her father hugged her and carried her. She is now scared in the next room," said one woman in western Baghdad who identified herself as Um Hanin. "All countries are stable. Why don't we have security and stability?"

While Baghdad and Iraq have gotten much safer over the years, explosions like Thursday's are still commonplace. They come at a precarious time in Iraq's political history, just days after American troops pulled out of Iraq.

The government of Prime Minister Nouri al-Maliki this week accused Sunni Vice President Tariq al-Hashemi of running a hit squad that targeted government officials and put out a warrant for his arrest. Al-Maliki is also pushing for a vote of no-confidence against another Sunni politician, the deputy prime minister Saleh al-Mutlaq.

Many Sunnis fear that this is part of a wider campaign to go after Sunni political figures in general and shore up Shia control across the country at a critical time when all American troops have left Iraq. Ayad Allawi, who heads a Sunni-backed party called Iraqiya, laid the blame for Thursday's violence with the government. The Iraqiya coalition also includes al-Hashemi and al-Mutlaq, and Allawi has been one of al-Maliki's strongest critics. Allawi warned that violence would continue as long as people are left out of the political process.

"We have warned long ago that terrorism will continue ... against the Iraqi people unless the political landscape is corrected and the political process is corrected, and it becomes an inclusive political process and full blown non-sectarian institutions will be built in Iraq," Allawi told The Associated Press, speaking from neighboring Beirut.

There was no immediate claim of responsibility for the morning's violence. But the coordinated nature of the assault and the fact that the attacks took place in numerous neighborhoods suggested a planning capability only available to al-Qaeda in Iraq.

Many of the neighborhoods were also Shia areas, which are a favorite target of al-Qaeda. The Sunni extremist group often attacks Shias who they believe are not true Muslims.

Al-Qaeda in Iraq is severely debilitated from its previous strength in the early years of the war, but is still able to launch coordinated and deadly assaults from time to time.

U.S. military officials have said they're worried about a resurgence of al-Qaeda after the American military leaves the country. If that happens, it could lead Shia militants to fight back and attack Sunni targets, thus sending Iraq back to the sectarian violence it experienced just a few years ago.