BAGHDAD: A new wave of insurgent attacks, mostly car bombs targeting Shiite-dominated cities in central and southern Iraq, killed at least 35 people on Sunday, officials said.

The attacks continue a surge in bloodshed that has engulfed the country for months, raising concerns of Iraq slipping back into the all-out sectarian war years earlier that left tens of thousands dead.

No one has claimed responsibility for the blasts, which targeted commercial areas and parking lots in seven cities.

The deadliest was in the city of Hillah, 95 kilometers south of Baghdad, where a car bomb explosion near an outdoor market and parking lot killed nine civilians and wounded 15 others, a police officer said. A few minutes later, another car bomb went off nearby, killing six civilians and wounding 14, he added.

In the nearby town of Iskandariyah, which lies 50 kilometers south of the country's capital, another car bomb hit a parking lot, killing four civilians and wounding nine, police officials said.

Moreover, another explosives-rigged parked car bomb went off in an industrial area of the Shiite city of Karbala, killing four and wounding 25, a police officer said. Karbala is 80 kilometers south of Baghdad.

In Kut, another Shiite-dominated city 160 kilometers southeast of Baghdad, a car bomb targeted a gathering of construction workers and food stalls, killing two and wounding 14, said a provincial police officer.

In Baghdad's northern Sunni-dominated Azamiyah neighborhood, a car bomb exploded near the convoy of the head of Baghdad's provincial council, killing three and wounding eight, police say. The council head escaped unharmed.

Two other car bombs hit the southern adjacent cities of Basra and Nasiriyah, killing five civilians and wounding 21, according to two police officers. Two more civilians were killed when a bomb hit a police patrol in Baghdad's western suburbs. Nine other people were wounded.

Eight medical officials confirmed the casualty figures, requesting anonymity as they were not authorized to release information.

Iraq is going through its deadliest bout of violence since 2008, raising fears the country is returning to a period of widespread killing such as that which pushed it to the brink of civil war following the 2003 US-led invasion.

More than 4,000 people have been killed in violent attacks since the start of April, including 804 just in August, according to United Nations figures.