(31 Dec 2012) SHOTLIST 1. Top shot of Shiite pilgrims walking towards Karbala to attend the religious festival of Arbaeen 2. Female Shiite pilgrims walking from Baghdad towards Karbala, carrying religious banners 3. Various of Shiite pilgrims walking 4. Close of feet 5. Iraqi armed security troops escorting pilgrims 6. Troops searching pilgrims 7. Pilgrims walking 8. Various of men preparing and distributing sandwiches free of charge 9. Military vehicles and pilgrims on road towards Karbala STORYLINE Thousands of Shiite pilgrims continued making their way by foot to Iraq's holy city of Karbala on Monday for the coming celebration of Arbaeen, marking the end of the 40-day mourning period after the date of the death of Imam Hussein, the Prophet Muhammad's grandson. Tough security measures had been put in place to try and counter the threat of violence. Many of the pilgrims made the 80 kilometre (50 mile) journey from Baghdad and other provinces, escorted by armoured vehicles, soldiers and ambulances. Insurgents have previously staged attacks on Shiites during the religious festival. This year's observance of Arbaeen takes place during a sensitive political period as tens of thousands of Iraqi Sunnis, angry over perceived second-class treatment by the Shiite-led government, have been staging protests across the country. Violence has declined overall in Iraq since 2007, though insurgents routinely target security forces and civilians, in particular Shiite Muslims, whose community has dominated Iraqi politics since Saddam Hussein's overthrow. The celebration of Arbaeen is to reach its climax on Thursday when pilgrims converge on Karbala where Imam Hussein was massacred along with about 70 followers by an army of Umayyads, their rivals for leadership of the Muslim community, during a 680 AD battle. Hussein's death cemented the split in Islam between Shiite and Sunni Muslims. Find out more about AP Archive: http://www.aparchive.com/HowWeWork Twitter: / ap_archive Facebook: / aparchives Instagram: / apnews You can license this story through AP Archive: http://www.aparchive.com/metadata/you...