After Daring Rescue, South Pole Workers Moved to New City; One in 'Poor' Condition

— -- The two sick workers who were rescued from the South Pole and brought to a clinic in Punta Arenas, Chile, have now been transported to another, undisclosed city. One of the patients, a female, was in poor condition, an employee at the Magallanes Clinic told ABC News.

The ailing U.S. workers were evacuated from the National Science Foundation’s Amundsen-Scott South Pole Station and flown to Chile on Wednesday night, according to the National Science Foundation.

The NSF did not disclose the details of the patients' conditions, but said the care they needed was unavailable at the South Pole research center.

A nurse at the clinic in Punta Arenas told APTN in Spanish that the woman was suffering from a "complicated" gastric issue. He said the other patient had suffered a heart attack, but was doing better.

Video of the patients' arrival at the hospital appears to show a man walking out of an ambulance and a woman being removed on a stretcher.

The NSF said the employees were seasonal staffers at the South Pole station.

The research foundation said the plane that had departed the South Pole early Wednesday made one stop at a British station on the coast of Antarctica on its way to Chile.

The Amundsen-Scott South Pole facility is in one the most remote areas of the planet. Planes avoid the region between February and October because of the dangers of flying in the pitch black and extreme cold.

It is currently midwinter in Antarctica and the bitter cold can freeze jet fuel. The sun will not rise again until August.

This is only the third rescue mission attempted in the past 60 years. In 1999 a doctor at the station diagnosed herself with breast cancer and was unable to get out, so she treated herself with chemotherapy.

ABC News' Joe Goldman and Ben Gittleson contributed to this report.