A newspaper operated by defectors from North Korea claims that Kim Jong-Un is gravely ill following heart surgery.
Daily NK, a speciality website run mostly by North Korean defectors, cited unidentified sources inside the isolated state saying Kim is recovering at a villa in the Mount Kumgang resort county of Hyangsan on the east coast after getting the procedure on April 12.
CNN writes that US intelligence services are monitoring reports.
Kim recently missed the celebration of his grandfather's birthday on April 15, which raised speculation about his well-being. He had been seen four days before that at a government meeting.
The National Security Council and Office of the Director of National Intelligence declined to comment when reached by CNN on Monday. CNN has also reached out to the CIA and the State Department for comment and sought comment from the South Koreans.
Gathering intelligence out of North Korea is notoriously difficult -- one of the most challenging targets for US intelligence.
Kim is only 36 years old, but South Korea's intelligence services claim he is increasingly obese and lives an unhealthy lifestyle of binge eating and drinking. Ann Fifield, the Washington Posts' Beijing bureau chief, tweeted that his poor health is now obvious and wrote last year that he was a "heart attack waiting to happen."