According to state prison records, Ronald 'Butch' DeFeo Jr., the man who inspired "The Amityville Horror" books and movies, died last Friday while imprisoned.

DeFeo, who murdered his entire family in 1974 in their Amityville home while they were asleep, served a 25-years-to-life sentence at the Sullivan Correctional Facility in Fallsburg for each of the six killings.

DeFeo was reportedly transferred to Albany Medical Center and was pronounced dead at 6:35 PM.

Ronald DeFeo Jr.'s cause of death is yet to be determined by the Albany County Medical Examiner's Office.

Nature of the Amityville Murders

Ronald DeFeo Jr.'s parents and four siblings were found dead in their beds on the morning of Nov. 13, 1974, after creeping in their rooms and shooting them. In total, he killed six of his family members.

According to reports, it took DeFeo about 15 minutes to complete the act. He initially tried to cover up for the murders by running into the street and yelling for help.

But when police arrived at the scene, they knew that something wasn't right. There were no signs of struggle, and even the neighbors didn't hear anything odd.

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The only sign that something was happening in that home was when their family dark continuously barked.

DeFeo's alibi of being at work when the killings happened was quickly dismantled under police scrutiny.DeFeo later pointed his finger at hitman Lou Falini and an unknown accomplice, saying that Falini forced DeFeo to watch him commit the murders.

Eventually, Ronald DeFeo Jr. confessed and told the police simply that "Once I started, I couldn't stop. It went so fast."

Here are other creepy facts about the entire "Amityville Horror" case that gained worldwide attention

Identical Positions

When all six victims were found, all of their bodies were lying on their stomachs, suggesting that they were arranged by DeFeo that way.

The police also determined that the rifle used didn't have a silencer, which meant that the gunshot should have woken the family up.

However, there was no sign of struggle, nor any sign of sedatives to knock the victims out.

Furniture Still There

In the first chapter of Jay Anson's book, "The Amityville Horror," the furniture that had been in the house when DeFeo committed the murders were reportedly still there when the Lutzes purchased it.

It was also still in the exact sample place it had been that night of the murders.

Lutzes Stayed for Less than a Month

George and Kathy Lutz and their three kids lived in the house for 28 days and never returned due to terrifying experiences.

Demonic Boy Pic

Ed and Loraine Warren, the famous paranormal investigators, we're able to capture a photo of what seemed to be a boy with glowing eyes in the doorway.

Many believe it's the spirit of John Matthew DeFeo, who was nine years old when his older brother murdered him.

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