Iraqi soldiers fighting to retake the largely Sunni city of Mosul from Islamic State are mounting Shiite flags on their vehicles and raising them atop buildings, stoking the sectarian divisions that Iraq’s government has vowed to repair.

The flags most often depict the visage of Hussein, the grandson of the Prophet Muhammad who is revered by Shiites as the defining symbol of their religion. Flying on tanks or over government checkpoints and homes in recently reclaimed Sunni villages, they often dwarf Iraqi flags next to them.

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