Authorities say a teenage runaway accused of attacking an 86-year-old Knox County woman could face more serious charges after the elderly victim died from her injuries.

Knox County Sheriff Jimmy "J.J." Jones says Dorothy Clark died around 5:30 a.m. Sunday at a Farragut nursing home where she was getting continued treatment.

David R. Pulley, 17, is accused of breaking into the elderly woman's home May 15 to steal money and guns.

Pulley told investigators he beat Clark, stripped her and tied her to a chair with telephone cords. Then, according to reports, he poured bleach on her in an attempt to set her on fire and cut her throat.

Authorities had been searching for Pulley since Nov. 29 when he ran away from the Johnson City Boys Group Home. He surrendered to deputies the night of the attack.

Officials say his charges will likely be upgraded to first degree murder.