Updated

Back-to-back explosions tore through tents housing Shiite pilgrims in southern Iraq Thursday, the deadliest in a wave of bombings that killed at least 43 people nationwide, officials said.

The attacks in Hillah began with a roadside bombing near tents set up for Shiites commemorating the 17th century death of the Prophet Muhammad's grandson, Imam Hussein. That was quickly followed by a car bomb targeting emergency response teams.

The explosions, which occurred in a busy commercial area, killed at least 29 people and wounded as many as 90, a police officer said, making it the deadliest attack in the city this year.

Twisted and charred vehicles were left outside damaged stores as shopkeepers collected their strewn merchandise from the bloodstained pavement. Hillah is 95 kilometers (60 miles) south of Baghdad.

Ali Hussein, 44, was walking near his house when he heard the two thunderous explosions near the commercial area about 200 meters (yards) from his house.

"I rushed to the blast site and I saw burning cars and pieces of flesh everywhere," said Hussein, who owns a grocery store. "There were small blood pools all around the place," he added, blaming the security forces who "should do better in order to protect the innocent people."

Just hours earlier, a parked car exploded near the shrine of Imam Hussein in the Shiite city of Karbala, killing six people and wounding 20, another police officer said.

Karbala, 90 kilometers (55 miles) south of Baghdad, is one of the holiest cities in Shiite Islam and the place where Imam Hussein and his brother, Imam Abbas, are buried. Hundreds of thousands of Shiites flock to their golden-domed shrines every year.

Such religious ceremonies have often been targeted by Sunni insurgents seeking to foment sectarian violence and undermine the Shiite-led government.

A suicide bomber also drove his explosives-laden car into a police checkpoint in the mainly Sunni city of Fallujah, 65 kilometers (40 miles) west of the capital, killing three policemen and wounding 11 others, a police official in the city said.

And in the northern city of Mosul, a parked car bomb went off as a police patrol passed, killing two people and wounded two, police said. Another police patrol was hit by a roadside bomb in the town of Balad Ruz, 70 kilometers (45 miles) northeast of Baghdad, killing one policeman and wounding six others.

In other violence, a roadside bomb killed an Iraqi soldier and wounded five others in Taji, north of Baghdad, and a parked car bomb struck a restaurant in Madain, southeast of the capital, killing a civilian and wounding 12 others, according to police.

Five health officials confirmed the casualty figures. All the officials spoke on condition of anonymity because they weren't authorized to release the information.

The nationwide death toll was the highest since Oct. 27 when 40 people were killed in a string of bombings and other attacks around the country.

Although violence has ebbed since the peak of insurgency several years ago, attacks are still frequent against security forces, government officials and civilians. No one claimed responsibility for Thursday's bombings, but car bombs, shootings and roadside devices are the hallmark of Al Qaeda in Iraq.