In this image provided by Morton County Sheriff’s Department, law enforcement and protesters clash near the site of the Dakota Access pipeline on Sunday, Nov. 20, 2016, in Cannon Ball, N.D. The clash came as protesters sought to push past a bridge on a state highway that had been blockaded since late October, according to the Morton County Sheriff's Office. (Morton County Sheriff’s Department via AP)

Three Hundred Injured Following Police Attack On Dakota Access Pipeline Protestors

20 mace canisters were fired by police in a period of five minutes at one point. The police also fired mace canisters at medics.