Initial rumblings began after North Korea's most important holiday came and went on April 15 without an appearance by Kim, which was unusual. Then Daily NK, an online publication based in South Korea that focuses on the north, reported that Kim had received a cardiovascular system procedure on April 12, and was being treated in a villa in Hyangsan County.
CNN was unable to confirm the report, but a US official said that Washington is monitoring intelligence that suggests Kim is in grave danger after undergoing a previous surgery. A second source familiar with the intelligence told CNN that the US has been closely monitoring reports on Kim's health. But a South Korean official told CNN that Kim is "believed to be in other parts of North Korea than Pyongyang with other North Korean top officials," and "no unusual signs supporting reports about his health conditions have been detected." It's rare for the South Korean government to divulge information about Kim's whereabouts.