Shi'ite pilgrims gathering at the Imam Hussein shrine during a ceremony marking Arbain in the holy city of Karbala in southern Iraq this week. Iraqi Shi'ites visit Karbala to perform the ceremony of Arbain on the 40th day after the Shi'ite holy day of Ashura, which commemorates the death of Imam Hussein in the Battle of Karbala in AD680. The ceremony this year was again held amid high security due to the military offensive against the Islamic State in Iraq and Syria terror group.