Detectives arrived at the apartment in Queens Village Thursday morning to find a 72-year-old man dead with stab wounds and the others unconscious.
Police say that during their brief conversation, the suspect, 30-year-old Jaimie Walker, told investigators he got in a fight with his father over the presence of the devil. He reportedly said his father hit him in the head with a cup before Walker responded by stabbing his father with a pair of scissors.
The suspect told detectives he saw black smoke escape his father's body, and that black smoke then entered his own body.
According to authorities, Walker then proceeded to poison the three remaining victims -- his 72-year-old mother, his brother, and his brother's wife -- with an unknown substance.
Tests are being conducted on water bottles recovered next to the bodies, as well as chemicals recovered in the apartment, where Walker is said to have lived with his parents.
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"Officers observed the man in the hallway acting very incoherently," NYPD Assistant Chief Joe Kenney said. "He made statements he had injured somebody inside the apartment. Emergency service unit officers were called to the scene and they made entry into the apartment, where they discovered an unresponsive 72-year-old male who was laying on the floor of the bathroom with what appeared to be multiple stab wounds about the body."
The three other victims were found in the living room, all laid out on a mattress, alive but unconscious.
Investigators at first suspected carbon monoxide poisoning, but they later ruled it out and said further analysis showed they were possibly poisoned.
Officers cordoned off the three-story building on Hempstead Avenue for most of the day.
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Walker, charged with murder and criminal possession of a weapon, is currently in the hospital undergoing a psych evaluation.
Police say there was no prior history of domestic violence or any other calls involving emotionally disturbed people from that location.
The investigation is ongoing.
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