WELLINGTON, New Zealand - Former American astronaut Buzz Aldrin, one of the first men to walk on the moon, has been evacuated by plane from the South Pole for medical reasons, officials said Thursday. They reported that he landed safely in New Zealand and is receiving treatment there.

Aldrin, 86, was visiting the South Pole as part of a private tourist group when his health deteriorated, the International Association of Antarctica Tour Operators said on its website.

It said he was taken as a precaution on the first available flight to McMurdo Station, a U.S. research center on the Antarctic coast. It described his condition as stable and said that his family had been informed of the situation.

The National Science Foundation, which manages the U.S. Antarctic program, described Aldrin as “ailing” and said he was flown on a ski-equipped LC-130 cargo plane to McMurdo. From there, he was flown to Christchurch, New Zealand, where he was transferred to a local medical facility for treatment, the foundation said in a statement.

Aldrin became the second man to walk on the moon in 1969 as part of the U.S. Apollo 11 mission.

Earlier this year, Aldrin wrapped up a non-stop 10-week book tour in the U.S. and the U.K. 

The Associated Press contributed to this report.