East Hampton Police were called to the vessel docked at the Montauk Yacht Club, on Star Island Road in Montauk, around 12 a.m. Tuesday, to respond to a 911 call from a man reporting a woman unconscious on the boat.
Police say good Samaritans attempted to perform CPR on the woman.
The woman, 33-year-old Manhattan resident Martha Nolan-O'Slatarra, was pronounced dead on the boat by first responders.
It is not yet known who discovered her body or who called police.
A preliminary investigation and exam were inconclusive regarding the cause of death, which will be determined by an autopsy conducted by the Suffolk County Medical Examiner's Office.
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