FORT WORTH, Texas (AP) -

An inmate serving 70 years in a North Texas drug case has pleaded guilty to the 1984 slaying of an elderly woman and was sentenced to 20 more years behind bars.
    
Prosecutors in Tarrant County say 59-year-old James L. Sanders pleaded guilty Tuesday to murder in a cold case finally solved with DNA evidence.
    
Fort Worth police on Jan. 6, 1984, responded to reports of a woman attacked at her home. Investigators say 82-year-old Elsie Deem Stuck was beaten but managed to call a friend, who summoned help. Stuck died several weeks later.
    
Detectives in 2008 requested DNA testing on Stuck's bedding and pajamas. A law enforcement database matched DNA evidence to Sanders, who was imprisoned for a Tarrant County drug conviction.