Bombs targeting Shi'ite pilgrims in Baghdad and police in southern Iraq killed at least 44 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 Qaeda are still potent, often targeting Shi'ite 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 Shi'ite pilgrims across Baghdad as they gathered to mark the anniversary of the death of Shi'ite imam Moussa al-Kadhim, a great-grandson of Prophet Mohammad.

In the southern city of Hilla, 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 Shi'ite city of Balad.

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 Shi'ite Muslim pilgrims.

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

Al Qaeda'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, Shi'ite and ethnic Kurdish blocks, feuding over their power-sharing accord.  - Reuters