The death of a 1-year-old boy at a Bronx day care earlier this month has been ruled a homicide.

The boy, identified by police as Nicholas Dominici, died of acute fentanyl intoxication, the city’s medical examiner said Friday.

Prosecutors said three other children who were also poisoned by opioid exposure at the day care had the effects reversed by Narcan. 

Four suspects have been charged in connection with the case, including 36-year-old Grei Mendez — the woman officials say owned the day care — and her husband, 34-year-old Felix Herrera Garcia, according to prosecutors.

Herrera Garcia was arrested on Tuesday in Sinaloa, Mexico. He faces charges of federal conspiracy to distribute narcotics resulting in death and possession with intent to distribute narcotics resulting in death.

Mendez and another suspect, Carlisto Acevedo Brito, 41, face federal charges of one count of conspiracy to distribute narcotics resulting in death and one count of possession with intent to distribute narcotics resulting in death. Both counts carry a mandatory minimum sentence of 20 years in prison and a maximum sentence of life in prison. 

A fourth suspect, Renny Antonio Parra Paredes, 38, faces one count of federal conspiracy to distribute narcotics resulting in death. The charge carries a mandatory minimum sentence of 20 years in prison and a maximum sentence of life in prison. 

Prosecutors say the four suspects conspired to distribute fentanyl at the day care center from at least July through September.

“Large quantities of narcotics” were kept at the site of the day care, including a kilogram of fentanyl stored on top of playmats, and more narcotics were hidden in “trap” compartments near an area where the children played and slept, according to a criminal complaint.