A suicide bomber struck a pro-government militia in the town of Taji north of Baghdad on Monday, said Pakistan's Daily Times, killing at least 22 people.
More from GlobalPost: Iraq: Police headquarters in Kirkuk attacked by suicide bomber
Local officials said over 40 people were injured in the blast, which comes a day after a similar strike in the north killed 16.
Police told Pakistan's Daily Times that the bomber snuck into tribal fighters' meeting disguised as a civilian and detonated the explosives as salaries were being handed out.
The government recently upped the payment allotted to pro-government fighting units, whose ranks include many Sunni Muslims, according to Agence-France Press.
Some saw the move as an effort to placate growing Sunni anger towards the country's Shiite government following weeks of mass protests over corruption and alleged discrimination.
Both Shiite and Sunni militiamen were killed in Taji in Monday's attack, according to AFP.