The bombs targeting a vegetable market exploded in rapid succession, lawmaker Husain Hamham said.
The market is in Jadidat al-Shat, a sub-district near Diyala's provincial capital of Baquba.
Political and sectarian violence have intensified in recent months, causing Iraqi and world leaders to fear Sunni-Shiite tension could mount and bring a return of a full-scale sectarian war.
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