ABC News September 20, 2023

Day care operator charged in baby's fentanyl death allegedly deleted more than 20K text messages

WATCH: Kilo of fentanyl stored at day care where 1-year-old died

A New York City day care operator allegedly deleted more than 20,000 messages between her and her husband sent from March 2021 to the day a 1-year-old boy died from fentanyl exposure at her facility, according to the federal criminal complaint.

Nicholas Dominici, 1, died on Friday and three other children, ranging in age from 8 months to 2 years, were hospitalized and treated with Narcan and are now recovering, police said. An analysis of urine from one of the victims confirmed the presence of fentanyl, officials said.

Before calling 911 about the unresponsive children, Bronx day care operator Grei Mendez allegedly made three other phone calls: one to a day care employee and two to her husband, according to the federal court documents.

New York Daily News via Getty Images
Police at the scene on Sept. 15, 2023, where at least one child died as a result of coming into contact with a poisonous substance at a day care center in the Bronx section of New York.
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Mendez and tenant Carlisto Acevedo Brito are now facing federal charges of narcotics possession with intent to distribute resulting in death and conspiracy to distribute narcotics resulting in death, according to federal prosecutors.

A kilogram of fentanyl was stored on top of children’s play mats used for napping, according to the federal court documents.

Courtesy DEA and the US Attorney’s office for the Southern District of New York
Evidence from the Bronx day care where a kilogram of fentanyl was stored on top of children’s play mats used for napping, where the child died and three other children were overcome on Sept. 15, 2023, in New York.

In a case that's "shocked the conscience of the city," the defendants allegedly "poisoned four babies and killed one of them because they were running a drug operation from a day care center," Damian Williams, U.S. Attorney for Southern District of New York, said at a news conference Tuesday.

"Every New Yorker should be outraged," said Frank Tarentino, special agent in charge of the Drug Enforcement Administration's New York Division.

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Flowers and candles placed at the scene of the day care center where a child died in the Bronx section of New York, Sept. 17, 2023.
MORE: NYC Mayor Eric Adams calls for 'national assault' on fentanyl epidemic following death of child at day care

Mendez and Brito were initially arrested on state charges, including murder, manslaughter and assault.

Since July, Mendez and Brito maintained large quantities of fentanyl "despite the daily presence of children, including infants," the complaint said. They also allegedly had machinery used to press and package drugs, prosecutors said.

Courtesy DEA and the US Attorney’s office for the Southern District of New York
A kilo press, part of the evidence from the Bronx day care where a kilogram of fentanyl was stored on top of children’s play mats used for napping, where the child died and three other children were overcome on Sept. 15, 2023, in New York.

Tarentino said fentanyl "is now in everything and everywhere, killing victims instantly and indiscriminately," and he called it "the most urgent threat in our nation."

Mendez and Brito were arraigned on the state charges Sunday night and held without bail. Williams said they are now in federal custody and face a maximum of life in prison if convicted.

Theodore Parisienne for NY Daily News via Getty Images
Carlisto Acevedo-Brito, a suspect in the day care death of 1-year-old Nicholas Dominici, was taken from the NYPD 52nd Precinct in the Bronx on Sept. 17, 2023.
New York Daily News via Getty Images
Grei Mendez, a suspect in the day care death of Nicholas Dominici, was taken from the NYPD 52nd Precinct in the Bronx, New York, Sept. 17, 2023.

Williams said authorities are still looking for a co-conspirator who has not been charged at this time.

"We're not done," Williams said. "Look out for more on that soon."

Mendez’s attorney said she was unaware drugs were being stored in her day care by Brito, her husband's cousin, to whom she was renting a room for $200 a week.

The day care was licensed on May 16 by the state’s Office of Children and Family Services, according to public records. It's listed as having a capacity for eight children from 6 weeks old to 12 years old.

City health inspectors conducted a surprise inspection of the facility on Sept. 6 and did not find any violations, according to City Health Commissioner Ashwin Vasan.

"I'm very sorry, but one of the things that my child care inspectors are not trained to do is look for fentanyl. But maybe they need to," Vasan said at a news conference Monday evening.

ABC News' Emmanuelle Saliba contributed to this report.