Sept. 20 (UPI) -- A woman who operated a daycare out of a New York City apartment and a man who lived there have been charged with federal drug offenses after four children under her care suffered fentanyl poisoning, including a 1-year-old boy who died.

Grei Mendez, the owner of the Bronx daycare, and Carlisto Acevedo Brito, who lived in the apartment's bedroom and purported cousin to Mendez's husband, were charged Tuesday in a Manhattan federal court with one count of conspiracy to distribute narcotics resulting in death and one count of narcotics distribution resulting in death.

The charges, each of which carry a mandatory minimum sentence of 20 years' imprisonment, stem from four children who received care at Mendez's center being hospitalized mid-day Friday.

Mendez, 36, had called 911 at around 2:40 p.m. concerning three unresponsive children between the ages of 8 months and 2 years at her center. The children were rushed to the hospital where a 1-year-old boy died and the other two received Narcan, treatment administered to counter opioid overdoses.

A fourth child who had been picked up two hours before Mendez had called 911 was also taken to the hospital after becoming noticeably lethargic and unresponsive.

All three surviving children were hospitalized with what federal prosecutors called in the criminal complaint "serious injuries."

A search of the apartment conducted after the three children were taken to the hospital uncovered 1 kilo of fentanyl located inside a bag stacked upon children's playmats in a hallway closet near the daycare's bathroom.

Two machine presses used to compress powdered narcotics into 1-kilogram bricks for distribution and sale were also found on the site along with other drug distribution paraphernalia, including vacuum bags and a vacuum sealer.

"Parents entrusted Grei Mendez with the care of their children," U.S. Attorney Damian Williams of the Southern District of New York said in a statement.

"As alleged, instead of diligently safeguarding the well-being of those children, she and her co-conspirators put them directly in harm's way, running a narcotics operation and storing deadly fentanyl out of the very space in which the children ate, slept and played. The disregard shown by Mendez and her co-conspirators for the lives of the children under her care is simply staggering," he said.

The complaint accuses the pair of distributing narcotics, including from the daycare, from at least July.

The court document also accuses Mendez of attempting to prevent law enforcement from discovering evidence of the narcotics operation by deleting approximately 21,526 message between her and her husband, identified in the complaint as CC-1, that were sent and received as far back as March 30, 2021.

A search of her phone also found that before calling 911, she called her husband twice, the second of which was answered. After calling 911, she placed several additional calls to her husband, and prior to emergency personnel arriving on the scene, surveillance footage retrieved by law enforcement shows CC-1 entering the daycare empty-handed and then exiting 2 minutes later with two shopping bags.

"The timing of CC-1's entrance and then swift exit out a back alleyway from the daycare ... while carrying shopping bags, is consistent with the behavior of an individual attempting to remove materials from the Daycare to avoid their discovery by law enforcement," the charging document states.

The search of her phone also recovered deleted messages between Mendez and CC-1 from the time when law enforcement were at the apartment. According to the complaint, Mendez told CC-1 via encrypted message that law enforcement were asking about him and he instructed her to say that he was working.

Messages law enforcement retrieved from the phone belonging to Brito, 41, indicate that he conversed with Mendez concerning drug transactions.

Both defendants waived their Miranda rights, and during an interview with police, Mendez denied that drugs were at the daycare and suggested the kilo presses were left by a prior occupant, according to the charging document. She also told investigators that no one, including her husband, had come into the daycare on Friday.

The pair were arrested Saturday.

"Tragedy doesn't begin to describe the events that took place at Divino Niño Daycare," DEA Special Agent in Charge Frank Tarentino said Tuesday in a statement.

"This death and drug poisonings are every parent's worst nightmare and clearly define the danger fentanyl poses to every New Yorker. Fentanyl kills indiscriminately, and the defendants' callous and irresponsible disregard to safety led to two of the most heinous acts imaginable, causing the death of a child and poisoning three other children.

"These crimes are unacceptable."