The bombings -- 18 in all -- are part of a wave of bloodshed that has swept across the country since April, killing more than 3,000 people and worsening the already strained ties between Iraq's Sunni minority and the Shiite-led government. The scale and pace of the violence, unseen since the darkest days of the country's insurgency, have fanned fears of a return to the widespread sectarian bloodletting that pushed Iraq to the brink of civil war after the 2003 U.S.-led invasion.
With two days left in July, the month's death toll now stands at 680, according to an Associated Press count. Most of those have come during Ramadan, the Muslim holy month of dawn-to-dusk fasting that began July 10, making it Iraq's bloodiest since 2007.
"Iraq is bleeding from random violence, which sadly reached record heights during the holy month of Ramadan," said acting U.N. envoy to Iraq, Gyorgy Busztin. He said the killings could push the country "back into sectarian strife," and called for immediate and decisive action to stop the "senseless bloodshed."
There was no immediate claim of responsibility for Monday's attacks, but the Interior Ministry blamed al-Qaida's Iraqi branch and accused it of trying to widen the rift between Sunnis and Shiites.
"The country is now facing a declared war waged by bloody sectarian groups that aim at flooding the country with chaos and reigniting the civil strife," the ministry said in a statement posted on its website.
Sunni extremist groups such as al-Qaida's Iraqi branch, known as the Islamic State of Iraq, frequently use coordinated blasts like those on Monday to try to break Iraqis' confidence in the Shiite-led government and stir up sectarian tensions.
The U.S. Embassy in Baghdad condemned Monday's attacks, and stressed that the United States "stands firmly with Iraq in its fight against terrorism."
Iraq's violence escalated after an April crackdown by security forces on a Sunni protest camp in the northern town of Hawija that killed 44 civilians and a member of the security forces, according to U.N. estimates. The bloodshed is linked to rising sectarian divisions between Iraq's Sunnis and Shiites as well as friction between Arabs and Kurds, dampening hopes for a return to normalcy nearly two years after U.S. forces withdrew from the country.
Monday's attacks stretched from Mosul in the north to Baghdad in central Iraq and Basra in the south.
In the capital alone, a dozen car bombs struck at least nine neighborhoods, all but two of them predominantly Shiite, in the span of an hour, killing at least 37 people, police said. The deadliest blasts hit the eastern Shiite slum of Sadr City, where two bombs killed at least nine civilians and wounded 33 others.
After the Sadr City explosions, ambulances raced to the scene, where rescue teams tended to the wounded and police tried to sift through the rubble. The twisted, mangled wreckage of cars littered the pavement, which in spots was stained red with blood.
Ali Khalil, a 36-year-old taxi driver, said he was passing nearby when the first bomb went off.
"I heard a thunderous explosion that shook my car and broke the rear window," Khalil said. "I immediately pulled over and didn't know what to do ... people were running or lying on the ground."
He said he rushed two wounded people to a nearby hospital before heading back to his home to stay indoors for the rest the day. Like many Iraqis, he blamed political infighting and incapable security forces for the deteriorated security situation.
A blast in the town of Mahmoudiyah outside of Baghdad killed three more people.
The wave of bombings also extended to Iraq's majority-Shiite south.
Car bombs that struck an outdoor market and near a cluster of construction workers killed at least seven civilians and wounded 35 in the city of Kut, some 160 kilometers (100 miles) southeast of Baghdad, while a blast near an outdoor market in the city of Samawa killed three and wounded 14, officials said.
Another car bomb in a marketplace in the oil-rich city of Basra, some 550 kilometers (340 miles) southeast of Baghdad, killed four people and wounded five, according to police.
Outside the northern city of Mosul, which has been a major flashpoint in the recent surge of violence, a suicide bomber rammed his explosives-laden car into a military post, killing one soldier and wounding three others.
On Monday night, police said three people died and nine others were wounded when a bomb went off inside a small cafe in Madain, about 20 kilometers (14 miles) southeast of Baghdad.
Health officials confirmed the casualty figures. All officials spoke on condition of anonymity as they were not authorized to release information.
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