Four children who overdosed on fentanyl at a Bronx day care center, including a 1-year-old who died, were exposed while taking naps on mats covering over a kilogram of the drug, authorities say.

Police found the drugs underneath mats where the children had taken naps in a back room of the center, as well as three kilo presses, devices used to package large amounts of drugs, NYPD Chief Detective Joseph Kenny said Monday.

Grei Mendez, the operator of the day care center, and Carlos Acevedo Brito, her cousin-in-law who rented a room inside the center, are now facing federal charges in connection with the overdoses. Both suspects are being held without bail on multiple charges, including manslaughter, depraved indifference to murder and criminal possession of narcotics.

Police were called to the Divino Niño day care center on Friday when several children seemed unusually lethargic after taking naps. A 2-year-old and an 8-month-old recovered after they were administered Narcan, but 1-year-old Nicholas Dominici died at Montefiore Medical Center. Another child who was exposed had been taken to the hospital earlier.

"One grain, two grains of fentanyl could take down a grown man, so even just the residue itself for a small child would cause the death," NYPD Commissioner Edward Caban said.

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Police seek husband of day care operator

Police are now seeking Mendez's husband after he reportedly fled the scene after authorities were called, according to WABC-TV. Mendez placed several calls to her husband before calling 911 when she discovered the children unresponsive, the report said.

Asked about the report, her attorney Andres Manuel Aranda told USA TODAY that Mendez placed calls in the aftermath of the tragedy to both police and her husband, as well as her supervisors and neighbors.

"I don't know what sequence of events transpired. But she did call him and she was asking for his help, and he disappeared," he said.

Aranda said Mendez had no knowledge of the presence of drugs in the day care center.

"Hopefully, the truth will come out because my client had no idea whatsoever that there were any narcotics in that location," Aranda said. "She feels horrible about what happened. She is very distraught and feels that children are victims, and she's a victim also."

The NYPD and the U.S. Drug Enforcement Agency are investigating whether Brito, who entered the U.S. from the Dominican Republic around the same time the day care center opened, could be involved in a broader drug operation that used the day care center as a front, officials said at a press briefing Monday.

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Day care center passed 3 routine checks

The day care center passed three routine checks by the health department, including one unannounced search on Sept. 6. Police also confirmed they had received no complaints from the community related to "drug transactions" at the center.

"One of the things my child care inspectors are not trained to do is look for fentanyl, but maybe we need to start," said New York Department of Health and Mental Hygiene Commissioner Ashwin Vasan.

Julie Gaither, an assistant professor of pediatrics at Yale School of Medicine, told USA TODAY that, given fentanyl's strength, just a small amount could cause a child's death.

"Fentanyl is 50 to 100 times more potent than heroin, which is in itself more potent than most prescription opioids," Gaither said. "It takes only a minuscule amount of fentanyl to kill a child and to send them into respiratory distress and respiratory arrest, and to become unresponsive very quickly."

A study released by Gaither earlier this year found that fentanyl was blamed in 94% of opioid overdose deaths in children in the U.S. in 2021, up from just 5% in 1999.

"It's growing, and it's no longer a problem just for the older teens, those who would be likely to misuse fentanyl," Gaither said. "We're increasingly seeing very young children exposed."

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