The unidentified man was found in the waters off of Grass Island around 2:40 pm., Tuesday, Nov. 29.
Suffolk County Police Homicide Squad detectives say the man, who was found floating in a foot of water, had died of an apparent drowning death.
The man was found unresponsive after the department received a 911 call, police said.
He was pronounced dead after being pulled from the water, officials added.
The man was transported to the Office of the Suffolk County Medical Examiner where an autopsy will be performed to identify the victim.
Detectives are asking anyone with information to call the Homicide Squad at 631-852-6392.
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