The incident occurred around 1:30 p.m. Saturday, Aug. 3, at Red Cedar Point near Hubbard County Park, the Southampton Town Police Department said.
The young girl was pulled back onto the boat, but the older woman was unable to get back into the boat, possibly may have suffered a medical condition and became unconscious, police said.
Southampton Town Police officers, Bay Constables, Suffolk County Police Aviation along with Hampton Bays Ambulance responded to the incident after receiving a 911 call.
Suffolk County Aviation was ultimately able to locate the drifting vessel and directed responding Marine units to the incident location where the woman was pulled from the water.
The woman was subsequently pronounced dead on the scene.
Southampton Town Police Detectives are investigating the incident.
The identity of the woman is being withheld until family can be appropriately notified.
This is a developing story. Check back to Daily Voice for updates.
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