Clashes break out as guards try to stop a ` ` massive prison break , '' officials say . 11 inmates and 6 guards are killed , ' public safety officials report . Violence has been reported at the prison in the past . In 2010 , prosecutors said prison authorities let out inmates so they could kill their rivals .
Clashes break out as guards work to stop a `` massive prison break , '' officials say . 11 inmates and 6 guards are killed , Durango public safety officials report . Violence has been reported at the prison in the past . In 2010 , prosecutors said prison authorities let out inmates so they could kill gang rivals .