Shi'ites were targeted in a wave of blasts and other attacks, while many of them were taking part in Ashura rituals. Overall, at least 50 people were killed and 131 more were wounded. This solemn holiday marks the martyrdom of Imam Hussein in the 7th century and has become a symbol of the Shi'ite-Sunni schism. Sunnis, however, also suffered casualties in today's violence. Millions of pilgrims are expected to arrive in the holy city of Karbala and will be easy targets for militants.
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