A former New York detective who moonlighted by working for a mafia family and helped fuel a mini-mob war on Long Island while trying to protect its gambling operations was convicted Wednesday of lying to the FBI. 

Hector Rosario, 51, a former detective for the Nassau County police on Long Island, was also acquitted of obstruction of justice, the top charge he had faced. The verdict came after a seven-day trial in Brooklyn federal court.

“Hector Rosario cared more about lining his pockets with Bonanno family money and protecting his own interests than his fidelity to the law,” said Nassau County District Attorney Anne Donnelly. “He disgracefully compromised the investigative work of his fellow detectives by tipping off a target and lied to federal agents as the walls were closing in on him.”

A former New York detective moonlighted by working for a mafia family and helped fuel a mini-mob war on Long Island while trying to protect its gambling operations. (Howard Schnapp/Newsday RM)

U.S. Attorney John Durham called Rosario, a 15-year police veteran, a “corrupt detective” who chose loyalty to the mob “over the public he was sworn to protect.”

He was interviewed by FBI agents in 2020 as they were investigating Bonanno and Genovese criminal activity in the suburbs east of New York City. He falsely stated he had no information about the mafia or illegal gambling spots, authorities said. 

Rosario was fired from the force in 2022. He was among nine charged after federal authorities busted the gambling racket.  (Rashid Umar Abbasi for Fox News Digital)

Rosario was fired from the force in 2022. He was among nine charged after federal authorities busted the gambling racket. 

His lawyers argued the case hinged on the unreliable testimony of mobsters now cooperating with prosecutors as they faced their own criminal charges.

The other mafia clans in New York are the Colombo, Gambino and Lucchese families. 

The Associated Press contributed to this report.