WHITE PLAINS, N.Y. (CBSNewYork/AP) — A woman who admitted stabbing her two young nieces at their home across from Martha Stewart’s estate was found not responsible Monday because of mental illness.

Lisa Turkki, 40, of East Syracuse
, is to be committed to a psychiatric institution. Her case will be reviewed every two years and if she is ever found to have recovered, she could be released, the district attorney’s office said.

With the agreement of the judge, prosecutors and defense, Turkki entered a plea of not responsible to charges of attempted murder, assault and weapons possession.

Turkki was babysitting Maeve Kelly, 7, and Annabel Kelly, 9, of Katonah, on July 31 while their parents attended a Dr. John concert at the Caramoor Center, a popular summertime music venue within walking distance of the house.

At about 9:20 p.m., Turkki called 911 and said she had stabbed her nieces. Police found the girls slashed and bleeding but conscious. They have recovered.

Turkki was arrested without incident.

According to court papers, Turkki told police she had driven to her sister’s home to kill her family but didn’t know why.

“I feel sorry for what I did to my sister,” she said, the papers show.

Turkki said she was “schizoaffective” and may have missed some medications, the papers say. A person with schizoaffective disorder can have hallucinations, delusions, mania and depression.

Turkki had faced a sentence of up to 25 years in prison if convicted of attempted murder.

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