It happened on Sunday, March 8 just before 10:30 p.m. on the North Fork, in Aquebogue.
Riverhead Town Police responded to 45 Pine Ave. to check on the welfare of the owner of the house, Lee Pedersen, who was found dead.
An autopsy by the Office of the Suffolk County Medical Examiner determined Pedersen, 69, died of a gunshot wound.
The investigation is continuing.
Detectives are asking anyone with information on this incident to call the Homicide Squad at 631-852-6392 or anonymously to Crime Stoppers at 1-800-220-TIPS.
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