CROWLEY — A sex offender described as a person of interest in the death of a veteran Colorado corrections officer has been transferred to a maximum security prison while the death is being investigated.

Miguel Alonso Contreras-Perez, 33, was serving 35 years to life at the medium security Arkansas Valley Correctional Facility when Sgt. Mary K. Ricard, 55, died Monday in what prison officials said was an assault involving an inmate in the kitchen area of the prison 45 miles east of Pueblo. Sgt. Lori Gann was critically wounded in the assault.

Department of Corrections spokeswoman Alison Morgan said Wednesday the Colorado Bureau of Investigation and the state Inspector General's Office are investigating but she declined to release details about how Ricard was killed or what circumstances led to the attack.