The 29-year-old suspect, identified as Ian Kazer, apparently got into an argument with the parents inside the Syosset Circle home after he was fired from his job earlier in the day.
Authorities say he stabbed both his 66-year-old mother, Frances Kazer, and his 69-year-old father, Howard Kazer, around 9 p.m.
His mother was stabbed in the upper torso and neck and died at the hospital, while his father was stabbed in the chest and is hospitalized in stable condition.
Ian Kazer is charged with second-degree murder and second-degree attempted murder.
Neighbors described a frantic scene, and area residents said they were shocked by the brutality of the alleged crime.
"She was a very, very nice lady," one neighbor said. "And the son, also, he would walk up and down, going wherever he was going. He was very polite to me. He would say hi. So I don't know exactly what happened, but I really feel bad for that family."
The New York City Department of Education confirms that Frances Kazer taught at John Bowne High School in Queens from 1978 until her retirement in 2010.
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