A judicial investigation into a prison in northern Brazil says 59 prisoners were killed there in the past year.
Video taken inside the Pedrinhas prison in Sao Luis in the state of Maranhao also showed the torture of an inmate by other prisoners and cases of beheadings.
The report has been sent to Brazil's Supreme Court. The BBC reports it says prison officers have lost control and punishment or retribution is dispensed on a daily basis by gangs.
Justice Minister Jose Eduardo Cardozo said last year that Brazil had "a medieval prison system''. Half a million inmates are occupying spaces for 300,000.
