CANNON BALL, ND - FEBRUARY 22: Campers set structures on fire in preparation of the Army Corp's 2pm deadline to leave the Oceti Sakowin protest camp on February 22, 2017 in Cannon Ball, North Dakota. Activists and protesters have occupied the Standing Rock Sioux reservation for months in opposition to the completion of the Dakota Access Pipeline. (Photo by Stephen Yang/Getty Images)
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Getty Images News Stephen Yang