The convicted killer who spawned the legend of “The Amityville Horror” has died in a New York prison.

Ronald “Butch” DeFeo, Jr., who was 69 years old, died at the Albany Medical Center on March 12, multiple news outlets are reporting. He had been taken there on February 2 from the prison in Fallsburg, New York where he was serving six sentences of 25 years to life for the murders of his father, mother, two sisters and two brothers on November 13, 1974. He was convicted on six counts of second-degree murder in 1975.

DeFeo’s cause of death has not yet been determined.

DeFeo tried to claim insanity at his trial, with his attorney William Weber claiming the murders were self-defense because DeFeo was hearing voices in his head that told him that his family was plotting to kill him. However, DeFeo was also a heavy drug user, especially heroin and LSD, and it was determined at his trial that he was aware of his actions the night of the murders.

Around the time that DeFeo was convicted of the murders, George and Kathy Lutz moved into the Dutch colonial home at 112 Ocean Avenue where the murders took place, with Kathy’s three children from a previous marriage. The Lutz family only lasted 28 days in the house, after they claimed they were driven out by malevolent paranormal forces within the home.

Their story was written as a 1977 horror novel The Amityville Horror by Jay Anson, which claimed to be “based on a true story.” The novel was a success and led to the 1979 horror film of the same name, which then spawned a horror franchise that is approaching nearly 30 films over the past 42 years.

Over the years, various owners of the Ocean Avenue home – which the DeFeo family had named “High Hopes” – have changed its physical appearance, losing its characteristic “evil eye” windows, and changed its actual street address in an attempt to keep horror fans and gawkers away from the home. It was also recently blurred from Google Maps’ street view as well.

WATCH: Jackie Barrett, who became the "spiritual advisor" to Ronnie DeFeo while he was in prison, shares with the Spooky Southcoast radio show her experiences with him:

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