Bomb attacks hit the Iraqi capital Baghdad and a village near the northern town of Baquba on Wednesday, killing at least 52 people, police and hospital sources said.
In the deadliest incident, a bomb blew up in a funeral tent where mourners were marking the death two days ago of a Sunni Muslim pro-government militiaman, police said. It killed 18 people and wounded 16 in Shatub, a village south of Baquba.
Two years after US troops left Iraq, violence has climbed back to its highest levels since the Sunni-Shi'ite bloodshed of 2006-2007, when tens of thousands of people were killed.
Al Qaeda-linked militants are pursuing a campaign of attacks, mostly directed at state targets, Shi'ite civilians and Sunnis seen as loyal to the Shi'ite-led government.
Half a dozen car bombs exploded across the Iraqi capital on Wednesday, mostly in Shi'ite districts, killing 34 people and wounding 71, police and medics said.
The violence occurred amid a continuing standoff between the Iraqi army and Sunni militants who overran the city of Falluja west of Baghdad more than two weeks ago in a challenge to Prime Minister Nuri al-Maliki's government.