A mother who tossed her toddler into the Hudson River thought she'd heard a dog speaking to her and another voice telling her to jump in the water, prosecutors said Friday as they agreed to let her resolve the attempted-murder case by agreeing to possible psychiatric hospitalization.

Now diagnosed with bipolar disorder, 35-year-old Devi Silvia had never exhibited symptoms until days before she threw her 21-month-old daughter — and herself — into the chilly water off Manhattan's Upper West Side in May 2010, prosecutors said.

But over the roughly four days beforehand, the former high school math teacher from India thought she saw a strange bright light coming from her bedroom door during the night, had the idea that God had sent someone to clean her kitchen and felt her 6-year-old and people at the child's school were giving her unusual and frightening looks, Manhattan Assistant District Attorney Kevin Wilson told a judge.

And on the morning when she and her younger daughter would end up in the river, she believed she heard a dog in a playground tell her she also was a dog and then heard a voice command her to leap into the river as she and the toddler walked alongside it.

"It is clear that (Silvia) was acting as a result of a psychotic break with reality due to her bipolar disorder" and didn't understand what was happening to her, Wilson said as he explained why prosecutors made a rare agreement to let her plead not guilty because of mental illness and face the potential of psychiatric hospitalization, not prison.

In a soft voice, Silvia acknowledged throwing daughter Jessica Prithiviraj into the Hudson.

"But I don't know what I was doing," Silvia said in English, with a Tamil interpreter by her side. The language is spoken in Sri Lanka and southeastern India, including her home state, Tamil Nadu, among other places.

Silvia will be assessed for possible commitment to a state mental hospital. She's due back in court for an update Jan. 11.

Such plea agreements — technically, "not responsible by reason of mental disease or defect" — are enshrined in state law for cases in which prosecutors believe an insanity defense would prevail. They are few: Silvia is one of only two or three people to reach a similar pact with Manhattan prosecutors this year. Statewide statistics weren't immediately available late Friday.

Silvia's lawyer, Daniel M. McGillycuddy, said she "was befallen by an infirmity that caused this conduct."

Silvia, a former math teacher in her homeland, according to a former lawyer, had been in the United States for several years because her husband was working here.

Witnesses saw Silvia abruptly toss Jessica into the river off a pedestrian pier and then plunge in herself, police said. When people on shore called out to Silvia, she waved back at them and seemed to paddle farther out, one witness said.

Jessica was blue and motionless and wasn't breathing when rescuers plucked her and Silvia from the roughly 50-degree water, prosecutors said. The girl recovered.

Prosecutors had initially argued the incident was a deliberate, spiteful ploy on the part of a lonely wife angry at her husband. Silvia was longing to return to India after several years of moving around the U.S. to follow her husband's jobs, and she was angry that he'd paid her little attention while tending to his hospitalized mother, prosecutors said at the outset.

A relative took Jessica and her older sister back to India after their mother's arrest.

After about three months in a psychiatric hospital jail ward, Silvia was released on $10,000 bail and was ordered to attend psychiatric treatment five days a week.


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