Authorities say the 21-year-old male inmate identified as the "alleged assailant" in the killing of a female corrections officer at Texas prison over the weekend allegedly attacked the woman as she entered a storage area near the kitchen.

Texas Department of Criminal Justice officials said Monday that the inmate was assigned to the kitchen area. Officials say the inmate had been convicted of aggravated sexual assault of a child under the age of 14 and had been in prison since 2011.

The inmate hasn't yet been charged in the Saturday death of Mari Johnson at the Robertson Unit, a prison in Abilene.

The Department of Criminal Justice's Office of Inspector General is gathering evidence and will present the case to the Jones County district attorney when the investigation is complete.