The incident happened just before 4 p.m. Sunday, July 14, at Outer Beach at Smith Point County Park in Shirley when good Samaritans pulled the unresponsive man from the water.
The man was transported to Long Island Community Hospital in Patchogue, where he was pronounced dead.
He has now been ID'd as Michael Petruzzo, age 64, who police say was undomiciled.
Detectives are asking anyone with information on this incident to call the Homicide Squad at 631-852-6392.
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