PENN HILLS (KDKA/AP) -- Police sources tell KDKA-TV News that an argument may have provoked a horrific double murder and the dismemberment of the elderly victim's bodies in Penn Hills.
The partial remains of 73-year-old Olivia Gilbert and her husband, 76-year-old Lamar Gilbert, were found in their home Tuesday night.
The woman's 49-year-old son, Frederick Harris III, is now charged with two counts of homicide and abuse of a corpse.
Harris moved in with his mother and stepfather last weekend, after investigators say his biological father kicked him out of his house when he allegedly tried to choke him.
Sources say an argument between Harris and his mother and stepfather may have led to the horrific crime.
Police say Harris recently purchased four 45-gallon trash cans at the Home Depots stores in Wilkins Township and East Liberty.
Some of the dismembered body parts were found in the trash cans at the Gilbert home on Suncrest Drive.
Some of the human remains may never be located, sources say, because Harris put them out with the trash, and they were already picked up and disposed of either in a landfill or recycling bin.
Police also say they found a note inside Harris' pocket as they took him into custody.
It read: "Hello Fred Thanks for house sitting and fixing up the place while we are on vacation. See You soon, tell everyone hello. Mt and Mrs Gilbert Lamar PS Don't answer the door for anyone."
Police did not say who wrote the note, or when it was written.
The Associated Press reports a district magistrate will arraign Harris during the overnight hours.
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