The North Korean leader's absence is raising eyebrows around the world. Who would be next in line for the top job?

Satellite images appear to show a train likely belonging to North Korean leader Kim Jong-un has been parked at his compound on the country’s east coast since last week.

The images come amid speculation about Kim’s health, caused in part by a long period out of the public eye.

Kim Jong-un is in “a vegetative state” in a coma following a botched heart operation, according to disputed reports.

The unverified claims – which follow online rumours of his death – emerged as a team of Chinese medical experts reportedly flew in to treat the North Korean despot, who has not been seen in public for two weeks, reports The Sun.

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Rumours intensified about Kim Jong-un’s condition as a the Chinese team including health care experts is dispatched into North Korea to treat him, Reuters reports.

The trip by Chinese doctors and officials to Pyongyang comes after reports the North Korean leader was in a critical condition after cardiovascular surgery.

A delegation including the medical staff and led by a senior member of the Chinese Communist Party’s International Liaison Department left Beijing for North Korea on Thursday.

The New York Post is reporting a vice director of HKSTV Hong Kong Satellite Television, a Beijing-backed broadcast network in Hong Kong, claimed that Kim was dead, citing a “very solid source”.

Her post on the Chinese messaging app Weibo has been shared widely on social media, according to a report in the International Business Times.

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

Kim Jong-un’s train has been parked at the Leadership Railway Station servicing his Wonsan compound since at least April 21, the website 38 North, citing an analysis of recent satellite photos of the area.

The website said that the approximately 250-metre train wasn’t present on April 15 but was present on both April 21 and 23.

“The train’s presence does not prove the whereabouts of the North Korean leader or indicate anything about his health, but it does lend weight to reports that Kim is staying at an elite area on the country’s eastern coast,” it said.

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.

Seoul has also repeatedly indicated that there have been no unusual signs that could indicate health problems for Kim.

That hasn’t stopped growing unconfirmed rumors and media reports about Kim’s health that have emerged since he missed an April 15 commemoration of the 108th birthday of his grandfather and North Korea founder, Kim Il Sung.

Earlier in the week, South Korean news site Daily NK reported Kim was recovering after undergoing a cardiovascular procedure on April 12.

US officials said they were told Kim’s condition was critical after the surgery, although President Donald Trump has since cast doubt on the report.

On Saturday there were reports from Japan that the North Korean leader was in a “vegetative state”.

Speculation about Kim’s condition has escalated in the two weeks since he was last seen in public, at a politburo meeting on April 11.

On April 15, he was conspicuous in his absence from birthday celebrations of the founder of the North Korean state, his grandfather and state founder Kim Il Sung.

Kim Jong-un is the third generation of his family to rule North Korea, and he hadn’t missed the April 15 event, one of the year’s most important for the North, since assuming power after his father Kim Jong-il’s death in late 2011.

On Thursday, President Trump told reporters he thought the report Kim was gravely ill “was incorrect” but declined to say if he had been in touch with North Korea.

US Secretary of State Mike Pompeo told Fox News when asked about Kim’s health, “I don’t have anything I can share with you tonight, but the American people should know we’re watching the situation very keenly”.

Kim Jong-un, whose age is either 36 or 37, is said to be a heavy smoker, and has gained weight since he succeeded his father in 2011.

He also may have hereditary cardiovascular disease.

Kim’s health is of crucial importance because of worries that the serious illness or death of a leader venerated with near godlike passion by millions of North Koreans could cause instability in the impoverished, nuclear-armed country.

Many experts in South Korea downplayed speculation that Kim is seriously ill. They also said North Korea won’t likely face a serious immediate turmoil even if Kim is incapacitated or dies because someone else like his influential sister Kim Yoo Jong will quickly step in, though the prospect for the North’s long-term political future would be unclear.

In 2008, his father Kim Jong-il suffered a stroke and was reportedly treated by Chinese and French medical specialists.

He died in 2011 from a heart attack at the age of 70.

North Korea’s founder Kim Il Sung, who the current Kim closely resembles, ruled the country until his death in 1994, aged 82.

Donald Trump made history when he met with Kim Jong-un, in Singapore in 2018, for the first-ever talks held between a North Korean leader and a sitting US president.

– with The Sun and New York Post

candace.sutton@news.com.au