Shia pilgrims, who have been frequently targeted in Iraq, have been observing the festival of Arbaeen.

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Syrian troops reportedly fired shells and automatic weapons in the northern Arbaeen and Mashaa al-Arbaeen districts on Monday.

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The blast happened in the run-up to Arbaeen, a Shia holy day.

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The attack took place around noon between the towns of Iskandariya and Mussayib, south of the capital, Baghdad, as hundreds of thousands of Shia pilgrims are making their way to Karbala for Arbaeen, one of the holiest Shiite events.

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