Darrin Spivey, 35, and his son Dillon Sanchez, 15, drowned Christmas Day in the popular cave diving location called Eagles Nest Sink.
Investigators said a hunter saw them as they prepared to enter the water, and Spivey's fiance, Holly King, contacted the sheriff's office when they failed to return.
"We sent divers down Christmas night, and they found Mr. Sanchez at 67 feet and Mr. Spivey at 127 feet," said Sheriff's Office spokeswoman Denise Moloney.
Deputies said Spivey was an experienced diver, but not a cave diver. Sanchez had no diving certification.
WTVT-TV, Tampa, reported an investigation is being conducted by the county medical examiner, and added officials are analyzing the equipment Spivey and Sanchez used.
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