Police on Saturday were called to 52 Greenmont Drive in Enola, where a man later identified as John Miller was arguing with his adult daughter, East Pennsboro police said.
Responding officers deemed the situation "civil in nature," and left the scene.
However, a short time later, police got a 911 call from Miller, saying he had shot and killed his wife and his daughter, authorities said.
Officers arrived on scene and Miller was taken into custody without incident.
Miller's daughter was found with an apparent gunshot wound to her head and dead on the kitchen floor, while his wife was found with two apparent gunshot wounds to the head in a bedroom, PennLive reports.
Miller's daughter, whose name is not being released, was found dead inside the home while his wife was taken to the hospital with life-threatening injuries after officers rendered first aid, police said.
Miller was lodged in the Cumberland County prison where he was arraigned on homicide charges.
Anyone with information is asked to call the East Pennsboro Township Police Department at (717)732-3633 and request to speak with Det. Cohick or Sgt. Shope
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