Autopsy results confirm a southern New Jersey man killed his wife and their young son before hanging himself inside their home.

Police at scene of murder-suicide in Pitman (KYW TV via Facebook)

But it's unclear why 49-year-old Francis Adolf committed the slayings. Gloucester County prosecutors have said he left writings indicating he intended to harm himself and family members but haven't provided details.

Pitman police found the bodies of Adolf, 44-year-old Bonnie Adolf and 6-year-old Francis Adolf Jr. in their home Tuesday. Autopsy results released Wednesday by the county medical examiner's office show the son died from strangulation and blunt-force injury to the head and the wife died from blunt-force injury to the head.

Prosecutor Sean Dalton says there was no reported domestic violence history involving the family. Neighbors say they're shocked and saddened.

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