The owner of the Bronx day care facility where a 1-year-old boy was exposed to opioids and died and another person were arrested and charged in connection to the boy’s death, officials said.

Carlisto Acevedo Brito, 41, and Grei Mendez, 36, were arrested and charged Saturday night with murder, manslaughter, assault and various drug charges, the NYPD said.

Police and prosecutors allege in a criminal complaint that Mendez owns and operates the Kingsbridge day care center and Acevedo Brito lives in a bedroom inside the building where the day care is located. They were taken into custody Saturday for questioning.

Four children at the day care center were poisoned by exposure to fentanyl, police and prosecutors allege in a criminal complaint.

When first responders arrived at the day care center Friday afternoon, they administered Narcan to three children who were "unresponsive and demonstrating symptoms of opioid exposure," NYPD Chief of Detectives Joseph Kenny said at a press conference early Saturday morning.

Two of the children — a 2-year-old boy and an 8-month-old girl — recovered, but Kenny said the 1-year-old boy was pronounced dead at Montefiore Hospital.

A different 2-year-old boy was taken home earlier in the day. At home, Kenny said the boy was "lethargic and unresponsive,” and the child was taken to a nearby hospital, where he was given Narcan and saved.

According to the criminal complaint, a urine sample from the 7-month-old girl tested positive for fentanyl, and additional toxicology tests for the other three children are pending. A one-kilogram white powdery substance inside a closet at the day care facility also tested positive for fentanyl, according to the criminal complaint.

Two kilo presses - a tool often used by dealers selling large amounts of drugs - were found at the day care center, according to the criminal complaint.

Mendez’s attorney, Andres Aranda, told NY1 that Mendez is being held without bail and will next be in court on Thursday. She was not required to plea at a Sunday court appearance, according to Mendez.

Aranda said Mendez had no knowledge of any narcotics in the apartment or any idea how fentanyl made contact with the children.

Mendez had been renting a room to Acevedo Brito for two or three months, according to Aranda, who said Acevedo Brito was the cousin of Mendez’s domestic partner.

Records from the New York State Office of Children and Family Services show the day care center was first licensed in May and is allowed to care for up to eight children between the ages of six weeks and 12 years. The center was inspected earlier this month and did not receive any violations.

"[Our] top priority is the health and safety of all children in child care programs and we are deeply saddened by this horrific tragedy. We cannot comment further on an active agency and law enforcement investigation," the New York State Office of Children and Family Services said in a statement Sunday morning.

“Unfortunately, you know, young kids get into things in the house and, you know, whether it’s prescription meds or illegal drugs, we do see poisonings and children exposed to these things from time to time,” Dr. Christopher Strother, director of pediatric emergency medicine at Mount Sinai Hospital, told NY1’s Dean Meminger on Sunday about the dangers of fentanyl and opioids when it comes to young children.

Mendez and Acevedo Brito both face the same 28 counts. They are listed below:

Murder: Depraved Indifference
Manslaughter: Person Under 11 Years Old
Manslaughter: Recklessly Causes Death
Assault: Cause Injury Thru Risk of Death (4 Counts)
Assault: Cause Injury During Felony (4 Counts)
Assault: Cause Serious Injury (4 Counts)
Assault: Recklessly Cause Serious Injury (4 Counts)
Criminal Possession of a Controlled Substance (3 Counts)
Criminal Possession of Controlled Substance/Narcotic
Criminal Possession of Narcotic Drug
Endangering the Welfare of a Child (4 Counts)