The violence started around 8 a.m., when a bomb exploded outside a popular restaurant in Baghdad's Mashtal neighborhood, killing four people, according to police and hospital officials. It blew out the eatery's windows and left several cars mangled in the blood-streaked street.
The deadliest attack was a 10 a.m. car bombing near the Ministry of Labor and Social Affairs in Baghdad's Qahira neighborhood. Seven people were killed.
Another car bomb exploded outside a restaurant near one of the main gates to the fortified Green Zone, which houses major government offices and the U.S. and British embassies. Six people died, including two soldiers. Thick black smoke could be seen rising from the area as ambulances raced to the scene.
At one point amid the chaos, authorities shut bridges spanning the Tigris River in the capital, hoping to thwart further attacks.
Car bombings, roadside blasts, suicide attacks and other mayhem were reported in other parts of the capital as well as in Taji, Tarmiyah, Baqouba and Iskandiriya. In the northern city of Mosul, a local police commander was killed along with two bodyguards by a suicide bomber.
The U.S. and Britain, the two countries that contributed the bulk of the troops for the 2003 war effort, condemned the attacks.
"The vast majority of Iraqis want to leave behind the violence of the past to build a peaceful and prosperous country," British Foreign Secretary William Hague said in a statement.
Amid the political tensions, Iraq's Cabinet decided Tuesday to postpone next month's local elections in two provinces dominated by Sunnis.
Anti-American Shiite cleric Muqtada al-Sadr blasted the decision and threatened to withdraw his bloc's support from the government.
"Staying in this government has become harmful and not useful at all," he said.
Associated Press writers Sameer N. Yacoub, Qassim Abdul-Zahra and Sinan Salaheddin in Baghdad and Raphael Satter in London contributed to this report.
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