The Amarillo Globe-News reports 48-year-old Gregorio Felan received life without parole after pleading guilty Thursday to capital murder in the April 2011 death of Lois Kimbrell.
According to the plea bargain, Felan waived his right to any future appeals in the case and prosecutor Mark Snider did not to pursue the death penalty.
The autopsy showed that the victim died of stab wounds and blunt force trauma to the head.
Snider says prosecutors don't know Felan's motive, adding, "We'll probably never know."
Borger is about 55 miles northeast of Amarillo.