Bronx day care provider and 2 others indicted on murder charges in 1-year-old’s death. The boy’s father gives a gut-wrenching statement

A Bronx day care provider, her husband and his cousin have been indicted on murder and other charges on suspicion of exposing four children – including a 1-year-old who died – to fentanyl at the day care center last month, the Bronx district attorney’s office said Thursday.

Grei Mendez, 36, her husband, Felix Herrera Garcia, 34, and Carlisto Brito, 41, each were indicted on second-degree murder and second-degree manslaughter charges in the death of Nicholas Dominici, according to court documents.

Authorities have said Nicholas and three other children – two 2-year-old boys and an 8-month-old girl – were exposed to what investigators believe was fentanyl September 15 at Divino Niño day care center in the Bronx, a borough of New York City.

Nicholas died that day. The three other children were hospitalized with acute opioid intoxication, authorities said.

Nicholas was supposed to graduate from kindergarten in four years, his father, Otoniel Feliz, said at an emotional news conference Thursday.

Feliz said he was looking forward to his son’s kindergarten graduation photo.

“But sadly, what I have is a reminder of his death,” Feliz said as he held up a photo from the 1-year-old’s memorial.

The three defendants also were indicted on charges of first-degree criminal possession of a controlled substance, four counts of first-degree assault, five counts of second-degree assault, criminal possession of a controlled substance and four counts of endangering the welfare of a child, according to court documents.

The defendants were arraigned and pleaded not guilty to the charges Thursday in Bronx Supreme Criminal Court, according to court documents.

Mendez, the operator of the day care center, will “continue to plead not guilty,” an attorney for her told CNN.

“She is really sad because of what happened to the children,” the attorney, Andres Manuel Aranda, said.

CNN has sought comments from attorneys for the other two defendants.

How the drug operation worked, according to officials

The defendants are alleged to have been mid-level drug dealers who would cut fentanyl with other drugs or even household items like baby powder, using pressing machines found in the day care center to get the drugs packed and ready for distributors, a law enforcement official previously told CNN on condition of anonymity.

Officials said a kilo of the poisonous and potent drug was stored on top of children’s play mats, and more fentanyl was found beneath trap doors inside a room where kids played and slept at the day care center, according to court records.

“A beautiful little boy lost his life and three precious children … became seriously ill from fentanyl poisoning,” Bronx District Attorney Darcel Clark said in a news release Thursday.

“This is a catastrophe. Our sorrow is matched only by outrage because these babies were shields to protect a narcotics operation. Nicholas’ death was entirely– excruciatingly – needless and avoidable. We will get justice for him, the other children and their families.”

Mendez and Brito – her husband’s cousin and a tenant who lived in a bedroom at the center, according to court documents – were arrested on September 16.

Herrera Garcia was arrested in Mexico last week.

Herrera Garcia got two phone calls from his wife after the four children began to show signs of an overdose on September 15, court documents show. Investigators say Mendez called him before she called 911, records show.

Minutes before emergency responders arrived to help the poisoned children, Herrera Garcia is seen on surveillance exiting a back door of the day care center with two shopping bags full of what appear to be drugs, officials said.

The defendants also face federal charges.

Mendez, Brito and Herrera Garcia were charged in federal court last month with conspiracy to distribute narcotics resulting in death and possession with intent to distribute narcotics resulting in death.

A fourth person arrested in the case, Renny Antonio Parra Paredes, 38, was charged in federal court last month with one count of conspiracy to distribute narcotics resulting in death.

CNN’s Jessica Xing contributed to this report.

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