Where is the supreme leader Kim Jong Un? This question has become the talk of the Pyongyang, who too have not seen the North Korean leader after April 11 and the state-media has unusually been silent.

Did Kim Jong Un die of a failed heart surgery? Is he in a vegetative state after a failed stent procedure? Or he is still alive and is simply holidaying at Wonsan where his train was spotted? These are some of the questions that everybody seems to be asking.

Amidst all this confusion, Anna Fields, a Kim Jong Un biographer said in a tweet post: "The rumors about Kim Jong Un's health aren't confined to the outside world. Pyongyang is abuzz with talk that something has happened to the "Respected Comrade." Helicopters have been flying low, people have been stocking up on supplies."

The rumor mill went crazy on Saturday after Vice director of HKSTV Hong Kong Satellite Television, which is a Beijing-backed satellite TV channel, told her 15 million followers on Weibo that her Kim Jong Un death claim was backed by a "very solid source."

Soon after this, a Reuters report informed that China has sent in a team including doctors to advise Kim Jong Un.

[Also Read: Not Kim Jong Un death but North Korea's nuclear arsenal being misused should concern us all]

These developments soon sent the media on a frenzy with many suspecting a regime change in North Korea as the Supreme Leader has not been seen in public since April 11. And his subsequent absence especially on April 15, which is an important day in North Korea to honor the founder of the country, Kim's late grandfather Kim Il Sung, has raised several questions.

Japanese media claimed that Kim Jong Un was in a vegetative after heart surgery. Reports indicate that Kim Jong Un underwent heart surgery and now doctors from China are at secret Hyang San Hospital. There also has been a viral image that claimed to show Kim Jong Un inside a glass coffin.

North Korea experts seem to agree on one thing though in the past there have been Kim Jong Un death rumors this time it feels different.

"We are potentially facing a serious crisis," Andrei Lankov, a respected historian of North Korea told The Washington Post, adding that he believes that something is "definitely wrong" with Kim.