North Korean leader Kim Jong Un is in "grave danger" after being admitted to hospital.

North Korean leader Kim Jong Un is receiving treatment after undergoing a cardiovascular procedure early this month, a South Korean media report says.

According to CNN, the United States is now monitoring intelligence that the North Korean leader “is in grave danger after a surgery, according to a US official”.

The US is monitoring intelligence that North Korean leader Kim Jong Un is in grave danger after a surgery, according to US official. He recently missed the celebration of his grandfather’s birthday, raising speculation about his well-being, @jimsciutto reports tonight on @CNN.

— Jeff Zeleny (@jeffzeleny) April 21, 2020

The 36-year-old has not been seen publicly since April 11, with speculation over his health mounting after his absence from a key anniversary event last week.

North Korea marked the anniversary of the birthday of its founding father and Kim’s grandfather, Kim Il Sung, as a national holiday on April 15, but Kim was not seen in attendance. In fact, April 15 – considered to be North Korea’s most important holiday – went by with no official comment on why Kim Jong Un was absent.

Reporting from inside North Korea is notoriously difficult, especially on matters concerning the country’s leadership, given tight controls on information.

South Korea’s Unification Ministry, which handles inter-Korean affairs, declined to comment on the report.

Due to the difficulty of accessing information in North Korea, it is not known how badly the country has been impacted by the coronavirus pandemic.

Kim's health has deteriorated in recent months due to heavy smoking, obesity and overwork, the Daily NK,  a speciality website run mostly by North Korean defectors, report said.

Daily NK 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 at a hospital there.

"My understanding is that he had been struggling (with cardiovascular problems) since last August but it worsened after repeated visits to Mount Paektu," a source was quoted as saying, referring to the country's sacred mountain.

Kim left for the hospital after presiding over a meeting of the ruling Workers' Party's politburo on April 11, where Kim was publicly last seen, the report said.

Pyongyang fired multiple short-range missiles last week which Seoul officials said were also part of the Kim Il Sung birthday celebration.

Such military events would usually be observed by Kim, but there was no KCNA report on the test at all.

The politician, who has been the Supreme Leader of North Korea since 2011, is one of the youngest world leaders.

- With AAP.

Feature image: Getty.

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