A nine-year veteran of the New York Police Department died of an apparent self-inflicted gunshot wound early Tuesday hours after federal investigators informed him he was the subject of a Homeland Security Investigations inquiry, law enforcement sources said.

Salvatore A. Buscemi was met by Homeland Security personnel at John F. Kennedy International Airport on Monday after arriving on a flight from Italy, sources said. He was subsequently placed on modified duty by the NYPD and required to surrender four firearms registered with the department.

Police were called to a West Islip home early Tuesday morning after a relative heard gunfire, according to sources. Officers discovered Buscemi with an apparent self-inflicted gunshot wound; he was pronounced dead at the scene. Investigators recovered a trove of additional weapons from the residence following his death, the sources said.

Suffolk County police declined to comment, saying the death is part of a "non-criminal" investigation. The NYPD did not immediately respond to a request for comment Tuesday evening. Homeland Security Investigations had not issued a public statement on the matter when contacted, according to the reporting.

The focus of the federal probe into Buscemi was not clear Tuesday. Federal inquiries into law enforcement officers can address a range of matters; officials in this case have not disclosed details publicly.

Buscemi had served with the NYPD for nine years, according to law enforcement sources. Authorities meeting him at JFK and the subsequent departmental actions — modified duty and surrender of service-registered firearms — were consistent with steps taken when officers become subjects of federal investigations, sources familiar with such procedures said.

The incident drew immediate attention because it involved a serving city police officer and a federal inquiry. No arrests or charges have been announced in connection with the matter.

NYPD uniformed officer

The news outlet reporting the death also noted that relatives and neighbors were notified and that investigators processed the scene. Officials have not released an official timeline or a public statement detailing the scope of the federal investigation or the items recovered from the home.

Anyone in crisis or struggling with suicidal thoughts can seek immediate help. New York City residents may call 1-888-NYC-WELL for free and confidential crisis counseling. People outside the five boroughs can call the National Suicide Prevention Lifeline at 1-800-273-8255 or visit SuicidePreventionLifeline.org.

There were no immediate indications of disciplinary or departmental outcomes related to this matter beyond the modified-duty status and surrender of registered firearms reported by sources. Further information may become available as federal and local authorities conclude their inquiries and release official statements.