Korean-American missionary Kenneth Bae has been transferred to a North Korean labor camp from a hospital, despite U.S. concerns that his health is worsening.

In an e-mail sent to VOA's Korean Service, a U.S. State Department official said Bae was transferred to a labor camp immediately after being discharged from his hospital on July 30.

"We remain gravely concerned about Bae's health, and we continue to urge [North Korean] authorities to grant Bae special amnesty and immediate release on humanitarian grounds," the e-mail said.

The State Department official also asked for Bae to be moved back to the hospital in the interim. The statement comes after Bae received a visit at the labor camp this week by officials from the Swedish embassy, which represents U.S. interests in North Korea in the absence of diplomatic relations between Washington and Pyongyang.

The consular visit to Bae is the 12th such meeting since his arrest in November 2012 and the first in almost four months.