Authorities in Pennsylvania say they're still trying to figure out the motive for a rare sororicide involving teen sisters. According to the Lancaster County District Attorney's Office, 14-year-old Claire Miller called 911 around 1am Monday and told dispatchers she had killed her sister, Lancaster Online reports. Court papers state that when officers arrived at the Manheim Township home, the "hysterical" teen was trying to wash her hands in the snow and kept repeating, "I stabbed my sister." She directed officers to a bedroom where 19-year-old Helen Miller had been stabbed in the neck with a large knife and had a blood-stained pillow over her head. Police and EMS personnel were unable to save her.
Authorities say police determined that the sisters' parents were asleep at the time of the incident. "This certainly is an incredibly tragic and unusual case," Lancaster County District Attorney Heather Adams tells Fox 43. "Our sympathies are with this family as they try to cope with the impact of this crime. Investigators will continue to process and analyze evidence to determine the circumstances that led to the victim’s death." Claire Miller, a ninth-grade student, has been charged as an adult with criminal homicide. She was taken into custody at the scene and is being held at Lancaster County Prison, which says she is "under constant observation by a dedicated officer." (Read more Pennsylvania stories.)