Prison guards caught an inmate in the border city of Ciudad Juarez practicing witchcraft in his cell, local media reported Wednesday.
Cereso Martin Oscar Guerrero, known as "The Witch," was offering to conduct spells for other inmates at the prison, the Juarez newspaper El Diario reported.
Guerrero is serving time for the killing two men in May.
Prison officials searching Guerro's cell found animal bones, a yarn doll with the name of a local judge on it and a piece of paper with what appeared to be a spell written on it.
Guards checked the cell after inmates complained that Guerrero had charged them for spells that didn't work.
Authorities transferred Guerrero to a high-security cell until his behavior improves, the paper reported.