A Deer Park drug dealer pleaded guilty Thursday to selling a batch of fentanyl to a West Babylon man who overdosed in March, Suffolk County prosecutors said.

Vito Frabizio,, 33, pleaded guilty to three counts of third-degree criminal sale of a controlled substance and one count of second-degree criminally using drug paraphernalia.

“This defendant exploited the addiction of the victim, who was trying to get clean, by selling him deadly fentanyl, which resulted in that victim’s death,” said Suffolk County District Attorney Raymond Tierney, who complained that bail reform laws forced his office to initially release Frabizio after arrest.

Anthony Rutkowski, Frabizio's Southampton-based defense attorney, did not respond to a request for comment.

Prosecutors said Frabizio sold two bags of heroin laced with fentanyl to Frank Cairo, 51, who was discovered on March 8 by his girlfriend dead in his bed where he was attending a virtual Narcotics Anonymous meeting.

At the scene, officers recovered two bags of narcotics, three hypodermic needles, and a cellphone belonging to Cairo, officials said.

Cellphone records showed that Frabizio sold fentanyl — a powerful synthetic opioid responsible for many of the latest overdose deaths on Long Island — and a heroin-fentanyl mixture to Cairo the previous day, prosecutors said.

On March 9, a Suffolk County police officer communicated with Frabizio and purchased one-eighth of an ounce each of fentanyl and cocaine during an undercover buy at the Sayville Motor Lodge, authorities said. During that purchase, the undercover officer observed additional quantities of narcotics inside the room, officials said.

Police executed a search warrant of the motel room, arrested Frabizio and recovered more than half an ounce of fentanyl, as well as cocaine, two digital scales and nearly $4,000 in cash, prosecutors said.

Frabizio was arrested again in West Babylon on March 25, along with co-defendant Joan Mangels, 40, of Amityville, after he sold fentanyl and cocaine to another undercover narcotics officer, records show.

Authorities recovered drugs and cash from the apartment.

Mangels’ case is still pending, records show.

Frabizio is scheduled for sentencing on Nov. 18.

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