A Springfield Township, Montgomery County, woman killed her parents, stabbing them and hitting them over the head, before killing herself, investigators said Thursday.

The bodies of Robert McIntyre and Sheila Dolan and their daughter Julia McIntyre were found late Monday by detectives conducting a wellness check at their home on Erdenheim Road, according to District Attorney Kevin R. Steele.

Autopsies completed this week showed that Robert McIntyre, 71, was killed by stab wounds to his neck and a blunt-impact injury to his head. Dolan, also 71, was killed by an “incised wound" to her neck — a forensic term for a cut made by a sharp object — and blunt-impact injuries to her head.

The manner of their deaths was homicide, according to Steele. Investigators say the couple were killed by Julia McIntyre, 27, who died of self-inflicted stab wounds to her neck.

Police were called to the family’s home by a relative who had become concerned after not hearing from the couple, according to a law enforcement source.