The target: the estranged half brother of North Korean leader Kim Jong Un. The setting: an airport in Malaysia. And the possible suspect: a woman carrying a cloth treated with lethal liquid.

It adds up to a case that seems ripped straight from the pages of a spy novel.

Even by the standards of sensational news from North Korea, the details that emerged Tuesday were astounding.

Malaysian police confirmed that Kim Jong Nam — who was thought to be 45 and living outside North Korea for more than a decade — was killed at Kuala Lumpur International Airport early Monday while waiting for a flight to Macau, a center of gambling and nightlife that was among his haunts.

“A woman came from behind and covered his face with a cloth laced with a liquid,” Police Chief Fadzil Ahmat told Bernama, the Malaysian state news agency.

(Jason Aldag/The Washington Post)

The man was seen struggling for help and sought assistance from airport staff, he said. He was sent to a hospital in an ambulance but died on the way, Fadzil said.

“I have conveyed the matter to the North Korean Embassy,” he said, adding that an autopsy was planned to determine the cause of death.

His statement came after South Korean news outlets reported an even more outlandish version of events: that Kim was pricked with poisoned needles by two female agents who then escaped by taxi.

Police have since announced the arrest of a female suspect carrying Vietnamese travel documents, according to news agencies.

[Defying skeptics, Kim Jong Un marks five years at the helm of North Korea]

North Korea, with its secretive and idiosyncratic leadership, is often the subject of dramatic tales that turn out to be exaggerated or flat-out wrong.

But the Malaysian police chief’s confirmation suggests that at least part of this story is true. What is likely to take much longer to determine is whether the plot was orchestrated directly by Kim Jong Un, who recently celebrated five years at the helm of North Korea and is now locked in a showdown with the international community over his nuclear ambitions.

1 of 22 Full Screen Autoplay Close EUROPEAN PRESSPHOTO AGENCY" data-title="March 29, 2013 " data-max-width="4096" data-image="https://www.washingtonpost.com/rw/2010-2019/WashingtonPost/2013/04/10/National-Security/Images/03644971.jpg?env=A" data-ratio="1.414"> Skip Ad × Aug. 19, 1981: Kim Jong Il with son Kim Jong Nam, front right, and other family members. The older son was once expected to succeed his father, but Kim Jong Un, his younger half-brother, ascended instead. View Photos His recent behavior and threats seem to have put the hermit state’s young ruler into a corner. Caption His recent behavior and threats seem to have put the hermit state’s young ruler into a corner. Feb. 16, 2012 A few months after his father's death, new North Korean leader Kim Jong Un reviewed a parade at Kumsusan Memorial Palace in Pyongyang commemorating what would have been Kim Jong Il's 70th birthday. David Guttenfelder/Associated Press Buy Photo Wait 1 second to continue.

Regardless, it underscores the transience of power in North Korea.

Just three years ago, Kim Jong Un had his uncle — and Kim Jong Nam’s mentor — executed on suspicion of building an alternate power base. Meanwhile, a slew of high-profile defections have raised questions about the stability of the regime.

“Kim Jong Nam was involved in some funny business,” said Michael Madden, editor of North Korea Leadership Watch, a specialist website devoted to the ruling Kim family. He was rumored to have worked in computing in North Korea — now notorious for cyberattacks — and money laundering throughout Southeast Asia.

Analysts had long considered Kim Jong Nam, as the eldest son of second-generation leader Kim Jong Il, to be the natural heir to the family dynasty.

But this assumption was thrown into doubt in 2001 when Kim Jong Nam was caught at Narita International Airport in Tokyo, trying to enter Japan with his wife and son on fake Dominican Republic passports. Kim Jong Nam’s bore the name Pang Xiong — “fat bear” in Mandarin Chinese. He told the authorities that they wanted to go to Tokyo Disneyland.

It was later revealed that he had never been in the running to be leader. Kim Jong Un’s aunt told The Washington Post last year that the current leader was chosen as successor in the early 1990s, when he was only 8 years old.

In 2010, with Kim Jong Il’s health steadily worsening, Kim Jong Un was officially declared heir apparent.

Both before and after the announcement, the usually reclusive Kim Jong Nam said in interviews with Japanese media that he opposed hereditary succession, something that not even Mao Zedong had done in China. “But I presume there were internal reasons. We should abide by such reasons if there are any,” he told TV Asahi.

[The secret life of Kim Jong Un’s aunt, who has lived in the U.S. since 1998]

Kim Jong Nam was born in 1971, the son of leader Kim Jong Il and his consort, an actress named Song Hye Rim. But he grew up largely in secret, the result of founding president Kim Il Sung’s disapproval of his son’s relationship with Song.

He left North Korea to live with his grandmother in Moscow in 1979, according to North Korea Leadership Watch. He spent his childhood at international schools in Russia and Switzerland before returning to North Korea in 1988, the site says.

But the embarrassing incident in Japan was a tipping point, and Kim appears to have never lived in North Korea again. He reportedly lived for a period in Macau, a Chinese region. But in recent years he seems to have had homes — and families — in Beijing and Singapore as well.

He was occasionally sighted in sushi restaurants in Singapore and swanky hotel bars in Beijing but otherwise kept a low profile.

Kim did, however, return to North Korea at least one time after his younger half brother assumed the leadership — for their father’s funeral at the end of 2011.

[Ex-diplomat: ‘I’ve known that there was no future for North Korea for a long time’]

Madden of North Korea Leadership Watch said Kim Jong Nam could have been involved in financing for the regime and could have run into problems as a result. But at the same time, Madden noted that Kim had publicly said he would do anything to help the new leader.

Their relationship probably took a turn for the worse in 2013, when the young North Korean leader ordered the execution of their uncle, Jang Song Thaek. Jang had been close to Kim Jong Nam and had reportedly backed him as successor.

Since then, analysts had suspected that China was keeping Kim Jong Nam in reserve as a potential replacement for Kim Jong Un, who has had strained relations with the Chinese leadership — and as a way to keep North Korea stable but make it friendlier to Beijing.

Ken Gause, a North Korea leadership expert at CNA, a research company in Arlington, Va., said there were at least three possible reasons Kim Jong Un would want to get rid of his half brother.

It could be that Kim Jong Un, who is only 33, is in the end stages of consolidating his leadership. “And when the consolidation phase comes to an end in totalitarian regimes, patronage systems can be targets for purges,” Gause said.

It could be a signal to China that Beijing doesn’t call the shots in North Korea. Or it could be a sign of an internal power struggle in Pyongyang.

“I think all of these are very possible,” Gause said.

Read more:

North Korea fires ballistic missile, first since Trump elected in U.S.

Ex-diplomat: ‘I’ve known that there was no future for North Korea for a long time’

Two more North Koreans said to defect, but don’t hold your breath for regime’s collapse

Today’s coverage from Post correspondents around the world

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