Search efforts remain underway for a passenger after a motorized vessel overturned south of Point Lookout.
Nassau homicide detectives are now investigating the death of 54-year-old John Costa after his boat capsized while navigating rough waters Saturday.
Three of the boat's passengers, including Coast, were rescued Saturday and taken to nearby hospitals, officials said.
Officials said the boat capsized Saturday morning in Reynolds Channel near Point Lookout. Four people were reportedly on board at the time.
Three of its passengers were rescued and taken to nearby hospitals, officials said. There has been no sign of the fourth passenger, Joseph Sparacio of Farmingdale.
The Coast Guard says a boat of good Samaritans assisted in rescue operations, finding and pulling to safety one of the passengers. The two other rescued passengers were found clinging to the boat's hull.
Police are now investigating what may have caused the boat to overturn.