North Korea’s American prisoner hospitalized after losing 50 pounds

The health of Kenneth Bae, an American citizen serving hard time in North Korea, has significantly deteriorated, according to his sister, Terri Chung, who spoke with CNN late Sunday.

Bae, a Christian missionary and former North Korea tour worker, was arrested in November and convicted by the hermit kingdom in April for "hostile acts to bring down its government."

He reportedly works on a farm eight hours a day, has lost more than 50 pounds, and has now been moved to a hospital.

"I think the last three months in the labor camp have certainly been very trying on both his mental and physical health," Chung told CNN by phone. "He's also under a tremendous amount of stress," suffering from back pain, leg pain and kidney stones. Bae also has diabetes.

The United States does not have an embassy in North Korea. Instead, its interests are represented by Sweden, whose representative there visited Bae in the hospital on Friday last week.

Since 2009 six Americans have been detained in North Korea. In previous cases high-profile Americans have visited the country to secure their release, as former presidents Bill Clinton and Jimmy Carter each did in 2009 and 2010, respectively.

But Bae has been there longer than any of his predecessors. The State Department recently asked Pyongyang to release Bae on humanitarian grounds. It has yet to receive a response.

The last time we saw Bae was in footage released by the pro-North Korean newspaper Chosun Sinbo. You can watch that video here: