Karim Kadim / AP

The scene of a car bomb attack in the Karrada neighborhood of Baghdad on Wednesday.

BAGHDAD -- Bombs targeting Shiite pilgrims in Baghdad and police in southern Iraq killed more than 70 people on Wednesday in a wave of attacks during a major religious festival, police and hospital sources said.

Violence in Iraq has eased since the height of the war, but Islamists tied to al-Qaida are still potent, often targeting Shiite pilgrims to try to inflame sectarian tensions that drove Iraq close to civil war in 2006-2007.

In Wednesday's attack on the capital, at least 18 people were killed when four bombs struck Shiite pilgrims across Baghdad as they gathered to mark the anniversary of the 8th-century death of Shiite imam Moussa al-Kadhim, a great-grandson of Prophet Muhammad.

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It was the worst day of violence since early January, when four bombs in Baghdad killed 73, and the latest in a spate of bombings on Shiite religious sites.

In the southern city of Hillah, two car bombs, including one detonated by a suicide bomber, exploded outside restaurants used by police, killing 22 people and wounding 38. Two more car bombs killed four people in the mainly Shiite city of Balad.

The Associated Press reported that the death toll was expected to rise.

Wednesday's attacks came at a sensitive time. On Sunday, at least six people were killed when two mortar bombs struck a Baghdad square packed with Shiite Muslim pilgrims.

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Earlier this month, 26 people were killed and more than 190 wounded when a suicide bomber detonated an explosive-rigged car outside a Shiite religious office in the capital.

Al-Qaida's Iraqi affiliate, Islamic State of Iraq, claimed responsibility for the attack on the religious office.

Political tensions have been high in Iraq since the last American troops left in December, with the country's fragile government, split among Sunni-backed, Shiite and ethnic Kurdish blocks, feuding over their power-sharing accord.

Reuters and The Associated Press contributed to this report. 

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