PICTURED: One kilogram of fentanyl stashed on top of play mats at Bronx daycare where one-year-old died – as owner is slapped with federal charges

A kilo of fentanyl was hidden on play mats in a Bronx daycare center, resulting in the death of a one-year-old boy.

Nicholas Feliz Dominici, who had been at Divino Nino Daycare for only a week, died Friday from fentanyl. Three other children became ill and were hospitalized, with one in critical condition.

Grei Mendez De Ventura, 36, the owner, and her alleged accomplice Carlisto Acevedo Brito, 41, have now been hit with federal charges.

The pair were charged Tuesday in Manhattan federal court with possession with intent to distribute narcotics resulting in death and conspiracy to distribute narcotics resulting in death.

According to a federal criminal complaint, a brick of fentanyl weighing one kilogram was found on children’s play mats and on a “kilo runner.”

Grei Mendez De Ventura, 36, the owner, and her alleged accomplice Carlisto Acevedo Brito, 41, have now been hit with federal charges.

Pictured: Nicholas Feliz-Dominici, 1, died Friday after ingesting fentanyl at a Bronx daycare

Prosecutors said De Ventura and her husband Brito’s cousin “used the daycare front to disguise their true operation: a fentanyl drug factory.”

The alleged drug duo was reportedly cutting the drugs near the area where the children were napping.

De Ventura reportedly stood on the sidelines while her cohort tapered off opioids. Some fentanyl particles flew into the air and the children may have inhaled the deadly drug, sources said.

Authorities found a kiloblock of fentanyl in the same room where the children were, the federal complaint said.

“Despite the daily presence of children, including infants, the defendants had retained large quantities of fentanyl there, including one kilogram of fentanyl stored on children’s play mats,” said a statement signed by Drug Enforcement Administration Special Agent in Charge Kyle Harrell.

While Brito’s room, which he rented for $200 a week, contained equipment indicative of a large-scale drug operation, according to police.

A ‘kiloper’, commonly used to re-compress powdered medicines, was discovered and two other presses were found in the nursery.

They are “often used by drug traffickers in ‘mills’ or other locations where narcotics are broken down, combined with fillers or other narcotics, and portioned for sale,” the affidavit said.

On Friday, before police arrived at the Morris Avenue apartment, De Ventura had called several people, including her husband, before calling 911 to get help for the children.

Detectives said they also found video footage of both the man and other people fleeing the daycare in the initial confusion with bags of unknown contents.

De Ventura and Brito stored large quantities of fentanyl “despite the daily presence of children, including infants,” according to the indictment.

A ‘kilopers’, typically used to re-compress powdered medications, was discovered and two other presses were found in the daycare center

Law enforcement sources believe the basement beneath the daycare where Brito lived was actually a drug front

The pair were initially arrested Sunday evening on state charges including murder, manslaughter and assault and held without bail.

But they are now in federal custody and face up to life in prison if convicted.

Damian Williams, the U.S. attorney for the Southern District of New York, said at a news conference Tuesday that the case has “shocked the conscience of the city.”

A third suspect is still being sought. Police have launched a manhunt for De Ventura’s husband, who is believed to be the “ring leader” in the drug operation, officials said.

De Ventura’s attorney claimed she was unaware Brito had stored medications in her daycare center.

She opened the childcare center in the Bronx earlier this year and passed a surprise inspection on September 6.

Divino Nino Daycare was registered under the city’s Department of Child and Family Services because it was considered a home-based business.

The data shows that the daycare center was registered to care for a maximum of 8 children between 6 weeks and 12 years old.

Feliz Dominici’s grief-stricken parents, Zoila Dominici and Otoniel Feliz, said the daycare was recommended by the Kingsbridge Heights Community Center.

The heartbroken couple, parents of four other children, were trying to come to terms with the unexpected and tragic death of their youngest child.

The boy’s distressed mother told CBS News in Spanish, “Look what happened. If I had known, I wouldn’t have brought him along.’

NYPD Chief Detective Joe Kenny said Monday that police “discovered one kilogram of fentanyl in an area used to give the children naps.”

He further explained that the fentanyl was “under a mat where children had previously slept.”

U.S. Attorney for the Southern District Damian Williams spoke Monday at the announcement of the new federal charges

Frank A. Tarentino III (photo) Special Agent in Charge of the Drug Enforcement Administration’s New York Division, which covers New York State, spoke at a news conference Monday about fentanyl and the babies exposed to the deadly chemical at a daycare center in the Bronx

According to Kenny, “One grain, two grains of fentanyl can knock out a grown man, so even the residue from a small child would cause death.”

According to reports, no previous complaints have been filed against Divino Nino Daycare.

But some neighbors were concerned about what was happening behind the apartment doors. An elderly neighbor said she had never seen children enter or leave the home.

‘It was a daycare center without children for a year. For a year she had a daycare without children, but people were coming in. But no babies?,” she told The New York Post.

She also revealed that De Ventura would not allow her own child to stay in the apartment where other children were being cared for.

‘A daycare center without children and men walking in and out. Yes, we knew something. We knew something, there was something not good going on there.”

“We all said, ‘Drogas.’ How could you not know that?’

She claimed De Ventura’s daycare started getting busier two months ago when she started having some children, including a baby two months ago, and then two more children a few weeks before the tragedy.