Battle for Mosul: Operation to retake Iraqi city from IS begins
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Peshmerga forces advance in the east of Mosul to attack Islamic State militants in Mosul.
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Tanks move past soldiers in military fatigues as the sun begins to set east of Mosul, where the Iraqi government launched a U.S.-backed offensive to drive Islamic State from the northern city, in this still image taken from video released October 17, 2016.
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A member of Peshmerga forces stands on a military vehicle in the east of Mosul.