NEW YORK -- The mother of two Bronx children who died from gas poisoning has been arrested and charged with murder.

Responding to reports of a gas leak early Friday morning, police found three people unconscious in an ninth-floor apartment at 1500 Noble Avenue. 

Police identified two of the victims as 5-year-old Trevor Noel, Jr. and 4-month-old Lillian Noel. Both were found unconscious and pronounced dead on the scene.

The mother, 29-year-old Lisette Bamenga, was also found unconscious with "minor lacerations" to her wrists, police said.  Police sources said she attempted suicide. She was taken to Jacobi Hospital, where she was in stable condition.

The mother forced her children to drink toxic wiper fluid, sealed the apartment windows with plastic and tape and turned on the gas stove, police sources told the New York Daily News.

Read original report on NBCNewYork.com

Authorities found an apparent suicide note the mother had written stating that she was taking her children “to a better place,” a law enforcement official told The wall Street Journal.

Neighbors in the Bronx apartment building called the event a "tragedy."

 "I'm trying to understand it because there's children involved," said Vickie Montalbo. 

Bamenga was charged Saturday with two counts of first-degree murder.

Bamenga is a schoolteacher at Public School 58 in Brooklyn, according to the Journal. She previously taught from September 2005 to August 2006 at PS 58 in the Bronx.

Bamenga’s boyfriend, a New York City police officer, returned from his Thursday night shift to find his two children dead, according to the Daily News.

NBCNewYork.com's Kat Creag and msnbc.com staff contributed to this story.

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