Park spokeswoman Vickie Carson says 67-year-old William Larry Martin of Bronson, Fla., became ill in the River Hall portion of the cave, about a mile-and-a-half into the tour.
Carson told that Martin, who was touring the cave with his family, had to be carried out on a stretcher.
Edmonson County Coroner Michael Alexander pronounced Martin dead at 1:18 p.m. CDT.
Carson said no one has died on a cave tour since the 1980s.
Source: Miami Herald