Kim Jong-Un's playboy half-brother has been killed by two female assassins who attacked him from behind with poison at an airport in Malaysia, it has emerged.

Kim Jong-nam, the eldest son of former North Korean dictator Kim Jong-il, died on his way to hospital after collapsing at Kuala Lumpur airport while waiting for a flight to Macau on Monday.

The 45-year-old is believed to have been targeted by North Korean operatives who are still at large amid reports they attacked him either with poisoned needles or toxic spray.

Eyewitnesses say he asked for help at an airport information point before being rushed to a medical clinic in the terminal. The two attackers hailed a cab and fled.

There is already speculation that the assassination was ordered by his estranged brother, North Korean tyrant Kim Jong-Un.

Jong-nam was known to spend a significant amount of his time outside the country and had spoken out publicly against his family's dynastic control of the isolated state.

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Kim Jong-nam (pictured), the 45-year-old oldest son of Kim Jong-il, has been killed in Malaysia, according to reports in the country

Hospital security personnel block the entrance of the Forensic department at the hospital, in Putrajaya. Malaysian police have confirmed Kim Jong-Nam died en route to hospital from a Kuala Lumpur airport

Reports, citing multiple government sources, said two women hailed a cab and fled immediately after Jong-nam fell sick

Malaysian police have confirmed the dead North Korean man is Kim Jong-Nam and that he was waiting for a flight with a passport under the name of Kim Chol. He has been caught in the past using forged travel documents.

Police official Fadzil Ahmat said that the cause of Kim's death had not been determined yet, but that a post mortem would be carried out on the body.

'So far there are no suspects, but we have started investigations and are looking at a few possibilities to get leads,' Fadzil told Reuters.

According to Fadzil, Kim had been planning to fly out on Monday when he fell ill at the low-cost terminal of the international airport.

'The deceased ... felt like someone grabbed or held his face from behind,' Fadzil said. 'He felt dizzy, so he asked for help at the ... counter of KLIA.'

Kim was taken to an airport clinic where he still felt unwell, and it was decided to take him to hospital. He died in the ambulance on the way to Putrajaya Hospital, Fadzil added.

South Korea's TV Chosun, a cable television network, reported that Kim had been poisoned with a needle by two women believed to be North Korean operatives who fled in a taxi and were at large, citing multiple South Korean government sources.

The playboy half-brother of Kim Jong-Un (pictured, centre) was killed by two female assassins with poisoned needles at an airport in Malaysia, it has been claimed

Kim Jong-nam (right as a boy), the oldest son of former North Korean dictator Kim Jong-il (left), died on his way to hospital after collapsing at Kuala Lumpur airport

Kim Jong-nam is the son of Kim Jong-il's first mistress Song Hye-rim (pictured)

'We don't know if there was a cloth or needles; the receptionist said someone grabbed his face, he felt dizzy,' police official Fadzil said, when asked about the nature of the reported attack.

South Korea's national news agency Yonhap quoted a source as saying agents of the North's spy agency, the Reconnaissance General Bureau, carried out the assassination on Monday by taking advantage of a security loophole between Jong-Nam's bodyguards and Malaysian police at the airport.

Malaysia is one of a dwindling number of countries that has close relations with North Korea. Malaysians and North Koreans can visit each other's country without visas.

Cheong Seong-Jang, senior researcher at Seoul's Sejong Institute think-tank, said Jong-Nam had been living in near-exile so it was unlikely that Jong-Un saw him as a potential competitor for power.

'But if Jong-Nam committed an act to damage Jong-Un's authority, I think it's possible that the Reconnaissance General Bureau may have directly conducted the assassination under the orders of Jong-Un since it has been in charge of closely watching Jong-Nam.'

Kim Jong-Nam was once considered heir apparent but caused embarrassment to his father Kim Jong-Il following a botched attempt in 2001 to enter Japan on a forged passport and visit Disneyland using a Chinese alias, Pang Xiong, which means 'fat bear' in Mandarin Chinese.

He reportedly feared for his life after falling out of favour with Pyongyang and has since lived in virtual exile, mainly in the Chinese territory of Macau.

Malaysian journalists gather outside the Forensics department at Putrajaya Hospital in Putrajaya, where the body of Kim Jong-Nam is believed to be kept

Kim Jong-Un took over as North Korean leader when his father died in December 2011. Jong-Nam did not attend his father's funeral.

The dictator has been trying to strengthen his grip on power in the face of growing international pressure over North Korea's nuclear and missile programmes.

The latest launch of a new intermediate-range missile on Sunday brought UN Security Council condemnation and vows of a strong response from US President Donald Trump.

Kim Jong-Nam, known as an advocate of reform in the North, once told a Japanese newspaper that he opposed his country's dynastic power transfers.

'LITTLE GENERAL' WHO FELL OUT OF FAVOUR WITH PYONGYANG They used to call him the 'Little General' but Kim Jong-Nam - once heir-apparent to his father and North Korea's then-leader Kim Jong-Il - fell from grace in 2001 after a spectacular blunder. On Tuesday, after more than a decade in exile from the North, Jong-Nam - the 45-year-old half-brother of current leader Kim Jong-Un - was widely reported by South Korean media to have been assassinated in Malaysia. Born from his father's relationship with actress Sung Hae-rim, Jong-Nam is known to have been a computer enthusiast, a fluent Japanese speaker and a student in both Russia and Switzerland. He lived in Pyongyang after finishing his overseas studies and was put in charge of overseeing North Korea's information technology policy. But the chubby eldest son of the supreme leader was already seen by Seoul experts as something of a political lightweight when in 2001 he fell out of favour. Jong-nam (pictured) was reportedly close to his uncle Jang Song-Thaek, once the North's unofficial number two and political mentor of the current leader He was embarrassingly detained at a Tokyo airport, trying to enter Japan to visit Disneyland on a false Dominican Republic passport, accompanied by two women and a child. Jong-Nam and his family afterwards lived in virtual exile in Macau, Singapore and China. Jong-Nam's half-brother Jong-Un took over as North Korean leader when their father died in December 2011. In an email exchange with a Japanese journalist published in 2012, Jong-Nam spoke disparagingly of Jong-Un, saying he lacked 'any sense of duty or seriousness' and warned that bribery and corruption would lead to North Korea's eventual collapse. In another exchange with the same reporter in 2012, Jong-Nam said: 'Anyone with normal thinking would find it difficult to tolerate three generations of hereditary succession.' Kim Jong-Nam was once dubbed the 'Little General', but fell out of favour with his father In October 2012 South Korean prosecutors said a North Korean detained as a spy had admitted involvement in a plot to stage a hit-and-run car accident in China in 2010 targeting Jong-Nam. In 2014 Jong-Nam was reported to be in Indonesia - sighted at an Italian restaurant run by a Japanese businessman in Jakarta - and was said to be shuttling back and forth between Singapore, Indonesia, Malaysia and France. In 2012 a Moscow newspaper reported that Jong-Nam was having financial problems after being cut off by the Stalinist state for doubting its succession policy. The Argumenty i Fakty weekly said he was kicked out of a luxury hotel in Macau over a $15,000 debt. Jong-Nam's son Kim Han-Sol studied at university in Paris. Back in 2012, when at school in Bosnia, he labelled his uncle Kim Jong-Un a 'dictator' in an interview. 'My dad (Jong-Nam) was not really interested in politics,' Kim told the interviewer when asked why his father was passed over for the dynastic succession in favour of his younger brother. Advertisement

In an email exchange with a Japanese journalist published in 2012, Jong-Nam spoke disparagingly of Jong-Un, saying he lacked 'any sense of duty or seriousness' and warned that bribery and corruption would lead to North Korea's eventual collapse.

In another exchange with the same reporter in 2012, Jong-Nam said: 'Anyone with normal thinking would find it difficult to tolerate three generations of hereditary succession.'

But he said several times over the years that he had no interest in leading his country.

Kim Jong-Nam was once considered heir apparent but fell out of favour with his father Kim Jong-Il following a botched attempt in 2001 to enter Japan on a forged passport and visit Disneyland

Kim Jong-Nam has since lived in virtual exile, mainly in the Chinese territory of Macau

'Personally I am against third-generation succession,' he told Japan's Asahi TV in 2010, before his younger had succeeded their father.

'I hope my younger brother will do his best for the sake of North Koreans' prosperous lives.'

If confirmed, Jong-nam's case would be the highest-profile death under the Kim Jong-Un regime since the execution of the leader's uncle Jang Song-Thaek in December 2013.

Born to Kim Jong-il's first mistress Song Hye-rim, he was persecuted by his father as he feared he could be a threat to the succession he had planned for Kim Jong-un.

HIGH-PROFILE POISON ATTACKS After the assassination of Kim Jong-Un's half-brother, here are some previous high-profile poison attacks, fatal and otherwise. Poison umbrella kills Bulgarian - September 1978: Georgy Markov, a Bulgarian dissident living in exile in London, is stabbed with a ricin poison-tipped umbrella as he is going home from his job with BBC World Service radio. He dies four days later. Hamas leader survives coma - September 1997: Israeli agents working in Jordan administer poison to the leader of the Palestinian group Hamas, Khaled Meshaal, who is living there. But the agents are captured and in order to obtain their release Israel is forced to provide an antidote. Meshaal survives after falling into a coma. Dioxin scars Ukraine's Yushchenko - September 2004: Ukrainian politician Viktor Yushchenko, campaigning against Russian-backed candidate Viktor Yanukovych for his country's presidency, is diagnosed with dioxin poisoning which disfigures his face. His supporters accuse the Russian secret service of being behind the incident. Yushchenko goes on to win the election. Arafat poison charges dismissed - November 2004: Palestinian leader Yasser Arafat dies in a French military hospital. French experts are unable say what had killed him, fueling accusations that he was poisoned by Israel. After a murder probe French prosecutors dismiss claims he was poisoned, after Swiss experts said they found high levels of radioactive polonium on his personal effects. Indonesian Munir's arsenic death - September 2004: Indonesian human rights campaigner Munir Said Thalib dies of arsenic poisoning after a flight from Jakarta to Amsterdam. A pilot is convicted of killing him on behalf of his country's intelligence services, but in October 2006 the sentence is quashed by the Indonesian Supreme Court. Polonium kills ex-spy Litvinenko - November 2006: Former Russian spy Alexander Litvinenko dies in agony after drinking tea laced with highly radioactive Polonium-210 at a London hotel, in a case which plunged Moscow-London relations into a deep chill. Advertisement

In 2014 it was reported that he was aware that his life was in constant danger because he criticised the Kim Jong-Un regime.

Another source claimed at the time that a North Korean agent had tried to assassinate Kim Jong-nam in Macau in 2011, but failed after a bloody shootout with his bodyguards. He fled to another city.

There was even speculation that Beijing was watching Kim Jong-nam's back for him, with a pencilled-in plan to install him as leader of North Korea should the regime of Kim Jong-un collapse.

He was reportedly close to his uncle Jang Song-Thaek, once the North's unofficial number two and political mentor of the current leader.

In October 2012 South Korean prosecutors said a North Korean detained as a spy had admitted involvement in a plot to stage a hit-and-run car accident in China in 2010 targeting Jong-Nam.

Three years ago he was reported to be in Indonesia - sighted at an Italian restaurant run by a Japanese businessman in Jakarta - and was said to be shuttling back and forth between Singapore, Indonesia, Malaysia and France.

In 2014 it was reported that Jong-nam was aware that his life was in constant danger because he criticised King Jong-Un (pictured)

Former North Korean leader Kim Jong Il (bottom left) poses with his first-born son Kim Jong Nam (bottom right), in this 1981 family photo in Pyongyang, North Korea

In 2012 a Moscow newspaper reported that Jong-Nam was having financial problems after being cut off by the Stalinist state for doubting its succession policy.

The Argumenty i Fakty weekly said he was kicked out of a luxury hotel in Macau over a $15,000 debt.

Last year South Korea warned of possible North Korean assassination attempts on its territory. It noted previous attempts to assassinate Hwang Jang-Yop, the North's chief ideologue and former tutor to Kim Jong-Il, who defected to the South in 1997 and died of natural causes in 2010.

However, in 2015 it was reported that Kim Jong-Un had given his illegitimate half-brother a job in North Korea's foreign ministry.

Kim Jong-nam was said to have been given work in the division that handles issues involving Japan and even went to a Japanese school.