Responding officers were met at the front door by Keith Knight, 60, who "had what appeared to be blood on his hands," Molinelli said.
Police moments later found the bodies of 84-year-old Victoria Knight and Ronald Victor Knight, 60, the prosecutor said.
They'd been stabbed several times, he said.
"A large amount of blood was observed throughout the kitchen, living room and hallway," Molinelli said, adding that it was "unclear what prompted the attacks."
Both victims were taken to area hospitals, where they were pronounced dead.
Knight, who lived with the two victims, was being held on $2 million bail in the Bergen County Jail.
He was charged with two counts of murder and one count of illegal weapon possession.
The stabbings on Ward Place across from the Teaneck Armory drew police from several area agencies late on Wednesday, Oct. 14. The Bergen County Sheriff's Bureau of Criminal Identification collected evidence.
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