SEOUL, April 21 (Yonhap) -- The United States is looking into intelligence that North Korean leader Kim Jong-un is "in grave danger after a surgery," CNN reported Tuesday.
CNN cited an unidentified "U.S. official with direct knowledge," but offered no further details.
The report came after a South Korean internet news outlet reported that Kim has been receiving medical treatment at a villa in the resort county of Hyangsan, outside of Pyongyang, following a cardiovascular procedure.
Speculation has arisen about what happend to Kim since he apparently skipped an annual visit to the Kumsusan Palace of the Sun on the occasion of the 108th birthday of his late grandfather and state founder Kim Il-sung last Wednesday.
Kim was last seen on April 11 in state media reports presiding over a political bureau meeting of the ruling Workers' Party on Saturday, calling for "strict national countermeasures to thoroughly check the infiltration of the virus."
Kim took over as leader after his father and late leader Kim Jong-il died in late 2011.
N. Korea's SLBM drive aimed at regime survival, military edge, negotiation leverage: analysts
N. Korea's suspension from Olympics augurs ill for Seoul's peace efforts
IOC suspension of N. Korea latest wrinkle in inter-Korean sports cooperation
Hotline restoration raises hopes for inter-Korean summit, resumption of nuclear talks
N. Korea's withdrawal from Tokyo Olympics dampens hope for renewing inter-Korean sports cooperation