Millions of Shiite Muslim pilgrims head to Iraq's Karbala to mark the death of Imam Hussein

Millions of Shiite Muslims have packed the streets of the Iraqi city of Karbala on their annual pilgrim to mark the death of Prophet Muhammad’s grandson, Hussein who became a symbol of resistance when he refused to pledge allegiance to the Umayyad caliphate, leading to his death in battle during the tumultuous first century of Islam’s history, and exacerbating the schism between Islam’s two main sects, Sunni and Shiite