Five car bombs struck in predominantly Shiite cities and districts in central and southern Iraq on Monday, killing 36 people and wounding dozens in the latest wave of violence roiling the country, Iraqi officials said.
No one immediately claimed responsibility for Monday's blasts but coordinated bombings in civilian areas are a favorite strategy used by al-Qaida in Iraq.
Since last Tuesday and including the latest deaths, at least 218 people have been killed in attacks and battles between gunmen and security forces that began with clashes at a Sunni protest camp in northern Iraq.
The deadliest attack on Monday was in the southern city of Amarah, where two parked car bombs went off simultaneously in the early morning near a gathering of construction workers and a market, killing 18 people and wounding 42, the police said.
That attack was followed by another parked car bomb explosion near a restaurant in the city of Diwaniyah, which killed nine people and wounded 23. At least three cars were left charred and twisted from the blast outside a two-story building whose facade was damaged in the bombing. Shop owners and cleaners were brushing debris off the bloodstained pavement.
Amarah, some 320 kilometers (200 miles) southeast of Baghdad and Diwaniyah, 130 kilometers (80 miles) south of the capital, are heavily Shiite and usually peaceful.
Hours later, yet another car bomb went off in the Shiite city of Karbala, killing three civilians and wounding 14, police said. Two early Islamic figures revered by Shiites are buried in the city, about 90 kilometers (55 miles) south of Baghdad.
And in the otherwise predominantly Sunni town of Mahmoudiya, about 20 miles (30 kilometers) south of Baghdad, a car bomb ripped through a Shiite neighborhood killing six people and wounding 14, another police said.
Ibrahim Ali, a schoolteacher in Mahmoudiya, said he was with his students in the classroom when he heard a thunderous explosion.
"We asked the students to remain inside the classrooms because we were concerned with their safety," Ali said. "The students were panicking and some of them started to cry," added Ali. He described burnt bodies and cars on fire at the nearby blast site.
The school was closed for the rest of the day and frightened students were told to go home. "We have been expecting this violence against Shiites due to the rising sectarian tension in the country," added Ali, the schoolteacher.
Four medical officials confirmed the casualty figures. All officials spoke on condition of anonymity because they were not authorized to talk to the media.
Sectarian violence has spiked since Tuesday, when security forces tried to make arrests at a Sunni Muslim protest camp in the northern city of Hawija. The move set off a clash that killed 23 people, including three soldiers.
In a sign of mounting worries over the deteriorating security situation, Iraqi authorities on Monday decided to close the country's only border crossing with Jordan, beginning on Tuesday. A brief Interior Ministry statement didn't elaborate on the decision, saying only it is "related to the country's domestic affairs."
Iraq shut the same border crossing in January, not long after anti-government protests erupted, citing unspecified security concerns. The route from Jordan passes through the overwhelmingly Sunni cities of Ramadi and Fallujah, west of Baghdad, which have been hotbeds of Sunni anger at the government. A protest camp straddling the Jordan-Iraq highway in Ramadi is the center of the protest movement.
On Sunday, the government suspended the operating licenses of pan-Arab broadcaster Al-Jazeera and nine Iraqi TV channels after accusing them of escalating sectarian tensions in Iraq.
That move drew a strong criticism from some of the news outlets and a sharp rebuke from Human Rights Watch. Qatar-based Al-Jazeera said it was "astonished" by the move.
Apart from Al-Jazeera, the decision affected eight Sunni channels and a Shiite one. Al-Jazeera was founded with support from the tiny, energy-rich nation of Qatar, which is a leading backer of rebels fighting in neighboring Syria and is accused by many supporters of the Iraqi government of backing protests in Iraq too.