As many as 32 people were killed Wednesday after a series of bombings across Iraq, security and health officials said, as tensions between rival Muslim groups ratcheted higher.

The attacks targeted mainly Shia areas of the capital, Baghdad, and the northern city of Kirkuk, Agene Frace-Presse reported.

The violence followed attacks which killed 16 people Tuesday, including 12 who were shot dead when gunmen shot up a row of alcohol shops in Baghdad, the news service said.

AFP said that while violence in the country peaked in 2006 and 2007, attacks have killed more than 200 people in each of the first four months of this year.

Car bombs and roadside explosives did the most damage, with 18 dead after a blast outside a cafe, Reuters reported.

“There were two bodies on the ground outside the building, people were shouting and it was a mess everywhere,” witness Rawaa Rahman told reporters.

The violence is at its worst since American troops pulled out of Iraq in 2011.

The perpetrators also targeted police officers and checkpoints, with at least three officers among the dead, according to Reuters.

Tensions between the ruling Shias and minority Sunnis are increasing, the Associated Press said.

No groups have claimed responsibility for the latest attacks, but the AP suggests the hallmarks of the attacks are similar to others carried out by Al Qaeda in Iraq.

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