A specialist medical team and death rumours: The bizarre mystery surrounding Kim Jong-un.

Speculation continues to swirl that Supreme Leader of North Korea Kim Jong-un is in serious danger health-wise following a cardiovascular surgery in early April.

In fact, #KimJongUnDead has been trending on Twitter worldwide on Sunday, sparking confusion over the 36-year-old’s health status.

So what exactly do we know? Reporting from inside North Korea is notoriously difficult, especially on matters concerning the country’s leadership, given tight controls on information.

But here’s everything we know about the current status of one of the youngest world leaders, Kim Jong-un.

How did the rumours start?

On April 21, a South Korean media report stated that North Korean leader Kim Jong-un was receiving treatment after undergoing a cardiovascular procedure in early April.

It came as the 36-year-old had not been seen publicly since April 11, and followed speculation of Kim Jong-un’s absence from a key anniversary event on April 15 – the birthday of North Korea’s founding father and Kim’s grandfather, Il-sung.

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.

The Daily NK, a specialty website run mostly by North Korean defectors, which relies on anonymous sources from inside the North, reported that Kim's health had deteriorated in recent months due to heavy smoking, obesity and overwork.

North Korea media has carried no report of Kim's public activity since April 11, adding weight to speculation that the 36-year-old might be critically ill.

Is Kim Jong-un dead?

No, this has not been reported by any credible source and has not been confirmed by the North Korean government. So, why is speculation mounting?

Over the weekend, a Hong Kong broadcast cited "a very solid source" in their report that Kim had died. Meanwhile, a Japanese magazine reported that the North Korean leader was in "a vegetative state". Again, neither of these conflicting reports have been confirmed.

Meanwhile, a train, likely belonging to Kim Jong-un, has been spotted at the leader's compound on the country's east coast.

The satellite photos released by 38 North, a website specialising in North Korea studies, doesn't say anything about Kim's potential health problems, but they do echo South Korean government intelligence that Kim is staying outside of the capital, Pyongyang.

The photos come as Reuters has reported China has dispatched a team of medical doctors and officials to North Korea "to advise on" Kim. It quoted three unnamed people familiar with the situation.

The delegation, led by a senior member of the Chinese Communist Party's International Liaison Department, left Beijing for North Korea on Thursday, it added.

Listen: Kim Jong-un's little sister: The woman who could rule North Korea. Post continues below. 

North Korea exerts extremely tight control on information about its leadership, making it virtually impossible for outsiders to find out what's going on at those senior levels.

The have not provided any comment on the reports of Kim's health, and the state-controlled media has not mentioned the leader's health status or location.

Who is his likely successor?

Kim Jong-un is the third generation of his family to rule North Korea. If the news about the health of Kim Jong-un is true, it could lead to a new leader for North Korea. And according to widespread western media reports, that new leader will be his little sister, 31-year-old Kim Yo-jong.

Kim Yo-jong is the youngest daughter of the former leader Kim Jong-il and the granddaughter of the founder of North Korea, Kim Il-sung.

Now, she is believed to be the vice director of the Department of Propaganda and Agitation for the Worker's Party, which is North Korea's only political party.

In October 2017, she was promoted by her brother, Kim Jong-un, to North Korea's primary decision-making body, Politburo – signifying their close relationship.

In March this year, Kim Yo-jong made her first public statement in which she condemned South Korea after Seoul, the capital of South Korea, led protests against a military exercise by the North. She likened South Korea to a "frightened dog barking".

"Such incoherent assertion and actions… only magnify our distrust, hatred and scorn for the South side as a whole," she said in a statement published by state media.

Feature Image: Getty.

You can read everything we know about Kim Yo-jong here. 

Sign up for the "Mamamia Daily" newsletter. Get across the stories women are talking about today.