Nijier Drakeford, 23, of Lithia Springs, is accused of having a six-inch shank, a homemade knife made from a white piece of metal, hidden inside his mattress on Jan. 20 at 1:30 a.m. at the Cobb County Adult Detention Center, according to an arrest warrant from the Cobb County Sheriff’s Office. Nijier is charged with items prohibited for possession by inmates – warden’s authorization. Nijier remains in custody…