The undated story appears on the website nymeta.co. It claims Roof was assaulted by two black inmates in his cell and taken to the hospital.
Charleston County Sheriff's Maj. Eric Watson told The Associated Press on Tuesday his office has been battling the fake story for about a year. Roof, a white man who is being held in solitary confinement for his own protection, was assaulted last year when a black inmate got through an unlocked cell door to reach him.
Roof's face and back were bruised. Watson says that's the only time Roof has been hurt in jail.
Roof's sentencing in the slayings of nine black parishioners is this week. He faces a possible death sentence.
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