Description:Iraqi officials say a relentless wave of bombings has rumbled across Baghdad and nearby towns, killing at least 56 people and wounding more than 200.
The more than a dozen attacks Tuesday - mostly car bombings - highlight increasing sectarian tensions in Iraq a decade after the war began.
The attacks came on the eve of the anniversary of the U.S.-led invasion, which started before dawn on March 20, 2003.(0:27)