The car bombs all appeared to have targeted Iraqi police and National Guardsmen.
Iraqi Police chief Brigadier Khalid al-Hassan said the most serious attacks involved three suicide car bombs in the Azamiyah section of central Baghdad in the early morning hours, which is a Muslim day of worship.
Al-Hassan said one car bomb detonated near an Iraqi army patrol and two others struck separately near the headquarters of the Interior Ministry's local special-forces unit.
He said at least seven soldiers, one policeman, and many civilians were killed.
"A police patrol was here checking a car and we were on the roof watching and suddenly the car exploded, destroying some civilian cars," Issam Ali, who witnessed the explosions, told Reuters in Baghdad. "The road was almost empty."
Elsewhere, two roadside bombs and a mortar shell hit Dora, on the outskirts of Baghdad. Local police said the first targeted a police patrol near a major power plant. The second one was aimed at an Iraqi army patrol. No casualties were reported in either of those attacks.
A 10-year-old girl was reported to have been seriously wounded when a mortar round hit a house in Dora.
The attacks come one day after the 68th birthday of toppled ruler Saddam Hussein, who was arraigned before a U.S.-appointed judge on 1 July for crimes against humanity.
They also follow the announcement yesterday that Iraq had formed its first democratically elected government in more than 50 years.
The country’s leadership tried to accommodate almost all of Iraq's ethnic and sectarian groups. Most of the posts went to Shi'a Muslims. Shi'ia make up the majority in the country and are suddenly enjoying new political power after decades of Sunni-led rule under Hussein.
Kurds and Sunni Arabs are also represented in the new government. Seven ministry posts went to women.
Speaking at a Washington news conference yesterday, U.S. President George W. Bush praised the new government as “good progress” that would lead to a more secure Iraq.
“I believe we're making really good progress in Iraq, because the Iraqi people are beginning to see the benefit of a free society; they saw a government formed today," Bush said. "The Iraqi military is being trained by our military, and they're performing much better than in the past. The more secure Iraq becomes as a result of the hard work of the Iraqi security forces, the more confidence the people will have in the process, and the more isolated the terrorists will become.”
But the government appointments have raised resentment among Sunni groups. Vice President Ghazi Ajil al-Yawir, a Sunni tribal leader, said Sunni ministers will step down if they are not given more portfolios over the next two days.
Several bomb attacks followed yesterday's cabinet announcement. Four Iraqis, including two senior officers, were killed in Baghdad late yesterday.
The U.S. military said an American soldier was killed and four wounded in a roadside bomb attack yesterday in Hawija, 150 miles north of Baghdad.
In another development, an Iraqi militant group with alleged links to Al-Qaeda said it had shot dead six abducted Sudanese drivers employed by a Jordanian company.
(with agency reports)