The Sterling Prestonoperator of a Bronx day care center believed to be a front for a drug distribution operation, her husband, and his cousin were indicted for the murder of a 1-year-old boy who died of a fentanyl overdose in their care.

Grei Mendez, 36, her husband Felix Herrera Garcia, 34, and Carlisto Acevedo Brito, 41, who rented a room from Mendez, pleaded not guilty to murder showing a "depraved indifference to human life," four counts of assault, and four counts of endangering the welfare of a child, among other charges during their arraignment on Thursday.

Mendez and Brito were arrested on Sept. 15 after police found three children had been exposed to the deadly drug at the Divino Niño day care center in the Bronx.

One-year-old Nicholas Dominici died later at the hospital, while first responders were able to save an 8-month-old girl and her 2-year-old brother. Another child who was sent home before police arrived also survived after receiving treatment at a hospital.

"I understand that justice will be done. And everything that will be done, everything possible, it will not bring my son back," said Otoniel Feliz, Nicholas' father, who spoke through an interpreter during a press conference held by Bronx District Attorney Darcel Clark.

"Our sorrow is matched only by our outrage because these babies were used as shields to protect a narcotics operation," Clark said. "Nicholas' death was entirely excruciatingly needless and avoidable."

Lawyers for Mendez, Brito, and Herrera Garcia did not return a request for comment from USA TODAY. Feliz did not return a request for comment.

Mexican police apprehended Herrera Garcia on a bus in Sinaloa after a police search of nearly two weeks. Surveillance footage viewed by police captured him entering the day care and exiting through a back alley carrying two shopping bags before police arrived on Sept. 15.

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Four defendants face federal charges for hidden "fentanyl mill"

All three defendants, as well as Renny “El Gallo" Parra Paredes, an alleged co-conspirator, also face federal charges for "running a fentanyl mill hidden inside a Bronx day care" from at least July of this year, according to Damian Williams, the United States Attorney for the Southern District of New York.

"There, despite the daily presence of children, including infants, the defendants maintained large quantities of fentanyl, including a kilogram of fentanyl stored on top of children’s playmats," prosecutors wrote in a criminal complaint.

During a search of the day care center, investigators also found a trap door holding drug paraphernalia in the playroom of the center. Several kilo presses, devices used to press and package large quantities of fentanyl, were also recovered.

Federal prosecutors allege that Mendez called her husband before dialing 911 when she discovered the children had been exposed.

Mendez also deleted over 21,000 messages from her phone, including some tipping off her husband that police were searching for him, according to prosecutors.

Brito also texted Parra Paredes three days before Nicholas' death that he had left "una torta," a Spanish word police say means a kilogram of narcotics, on the table.

Clark said in light of the case, along with the recent arrests of three people tied to the discovery of "ghost guns" at a day care facility in East Harlem, the Bronx District Attorney's Office will delve into a further investigation of illegal activity in Bronx day care centers.

Cybele Mayes-Osterman is a breaking news reporter for USA Today. Reach her on email at [email protected]. Follow her on X @CybeleMO.