Ocean swells, shoulder pain and asthma dogged her before she was finally brought aboard a boat, vomiting, at about 12:45 am, the cable news network said.[break]
"I am not sad. It was absolutely the right call," she was quoted as saying.
Nyad, who had said she hoped to bring Cuba and the United States closer together, began her second attempt late Sunday to make the difficult crossing through the treacherous Florida Straits.
Had she succeeded, she would have been the first person to have crossed without a shark cage, CNN noted.
Nyad had already made a first attempt in 1978, which she was forced to abandon by poor weather.
The United States has not had diplomatic relations with Cuba since 1961 when it slapped a trade embargo on the communist-ruled island.

(FILE PHOTO, AFP)
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