The endurance athlete Diana Nyad abandoned her attempt to swim from Cuba to Florida yesterday with her face and body swollen from jellyfish stings. Doctors warned that another sting could be fatal.
A member of Ms Nyad's team said the swimmer was disappointed and emotional.
On Saturday she was treated aboard a support vessel for a jellyfish sting, but had returned to the water.
The 62-year-old swimmer had completed at least 49 miles of the 103-mile crossing of the treacherous Florida Straits.
Ms Nyad tried the marathon swim last month, but had to quit after a serious asthma attack. AP