Police officials say the attack took place today afternoon as people were delivering food to the Shiite pilgrims heading to the holy city of Karbala to mark the religious holiday of Ashoura.
They say the blast wounded 32 people. Medical officials confirmed the casualty figures. All officials spoke on condition of anonymity as they weren't authorised to speak to journalists.
Ashoura commemorates the seventh-century death of Imam Hussein, a grandson of Prophet Muhammad, and an iconic martyr among Shiite Muslims. Sunni insurgents frequently target Shiites whom considered as heretics.