Software company founder John McAfee was taken to hospital on Thursday after being denied political asylum in Guatemala.
McAfee told The Associated Press that he suffered chest pains overnight but didn't believe he had a heart attack.
A government doctor said he appeared to be suffering from high stress.
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The paralympian posted a time of two minutes and 57 seconds on Sunday.
The 17-year-old posted a supportive Instagram message accompanied by a childhood photo.
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