Florida authorities believe there is "no question" the two-year-old boy dragged into a man-made lake by an alligator at a Disney resort hotel in Florida is dead, Orange County Sheriff Jerry Demings said Wednesday.

Rescuers were still working to recover the body, Demings told reporters.

"We're 15 hours in," Demings said. "We know that that happened and it certainly is not survivable at this point for him to have been submerged for this period of time."

"There's no question they will lose a two-year-old child," he said of the boy's family, who had come to Florida from Nebraska for a vacation.