Was it brother? Lover? Or crime gang? North Korea rumors abound 

In this May 4, 2001, file photo, a man believed to be Kim Jong Nam, the eldest son of then North Korean leader Kim Jong Il, looks at a battery of photographers as he exits a police van to board a plane to Beijing at Narita international airport in Narita, northeast of Tokyo. Kim was assassinated at an airport in Kuala Lumpur, telling medical workers before he died that he had been attacked with a chemical spray a Malaysian official said Tuesday. AP FILE PHOTO

SEOUL, South Korea — As Malaysian police continue their inquiry into the death of Kim Jong Nam, the outcast half-brother of North Korean leader Kim Jong Un, there’s plenty of speculation surrounding what seems one of the stranger killings the world has recently seen.

North Korea killed Kim Jong Nam because he planned to create an exile government around defectors, says one rumor. Kim Jong Un was furious after learning about secret Chinese plans to enthrone his estranged sibling in Pyongyang if something happens to him, says another.

Or maybe Pyongyang wasn’t involved at all. Perhaps, Kim Jong Nam, known for his carefree lifestyle and gambling habits, angered crime organizations over money problems and that got him killed, say some online arguments.

Some theories are more bizarre. South Korean newspapers have reported on rumors making rounds on the Chinese internet that impeached South Korean President Park Geun-hye, who faces a court ruling on whether she should permanently step down over a corruption scandal or be reinstated, plotted Kim’s death to create a distraction.

South Korea’s spy agency, which has consistently described Kim Jong Un as an irrational and unstable dictator, argues that he killed a non-threatening sibling out of “paranoia.” The fuming North Korean ambassador to Kuala Lumpur says the country will reject the autopsy results on Kim Jong Nam because Malaysian officials may be “trying to conceal something” and “colluding with hostile forces.”

READ: Who assassinated Kim Jong-un’s half-brother?

While imaginations run freely, most South Korean experts think there’s a straightforward explanation behind the alleged assassination of Kim, who appears to have been killed by two women at a Kuala Lumpur airport on Monday in what has been suspected as a poison attack.

Kim Jong Un, who has executed or purged a slew of high-level officials since taking power in 2011, most likely made another move to remove a potential challenger to his power, the experts say. Kim Jong Nam had been the only member of the Kim clan who regularly talked to foreign journalists and sometimes went so far as to openly criticize the country’s hereditary power transfer.

North Korea has been seen as tightening control on its high-profile individuals overseas since the defection of Thae Yong Ho, a senior North Korean diplomat in London who arrived in South Korea last year. There’s also a possibility that Kim Jong Nam, who continued to stay in Macau and the Chinese mainland, was taken out because he disobeyed orders to return home, according to some experts.

But others find North Korea’s involvement hard to believe. Both of the women arrested for suspected involvement in the killing were non-Koreans and some think their methods were too unorthodox and careless to be considered a North Korean hit job.

“(The attack on Kim) was unbelievably sloppy,” Kim Jongdae, a South Korean lawmaker, told a radio interview. He pointed out that one of the women reportedly got arrested by returning to the scene a day later with the same clothes.

“Kim Jong Nam led a free-wheeling life, and loved to travel, and mingle with women … He might have had problems with crime organizations. Or maybe this was a crime based on a love affair gone bad,” he said.

Seo Jae Pyoung, a North Korean defector and anti-Pyongyang activist, thinks it’s unlikely that Kim’s death involved crime organizations. While Kim was believed to have profited from helping Chinese firms trade with North Korea when his father and the North’s second leader Kim Jong Il was alive, he probably stayed away from risky business activities after Kim Jong Un came to power, Seo said.

While some think the attack on Kim Jong Nam was careless, others see it as ingenious. It’s possible that the women might have not even known they were part of an assassination attempt — one of the detained female suspects reportedly told police she was tricked into thinking she was part of a TV comedy show prank.

“Whoever did it came up with a careful plan that effectively concealed criminal intent until the job was done,” said Koh Yu-hwan, a North Korea expert at Seoul’s Dongguk University. “That person had great understanding of how Western TV media works.”

Getting foreigners to do the job, rather than directly using its own operatives, might have been a logical choice for North Korea because it will likely continue denying involvement.

North Korea used its own operatives when it set off a bomb meant for then-South Korean President Chun Doo-hwan during a 1983 visit to Burma. Although Chun narrowly escaped the blast, more than 20 people were killed, including several of Chun’s Cabinet ministers and top aides. One North Korean agent was shot dead by police, a second one was sentenced to death and executed, and a third reportedly died in Myanmar prison in 2008.

Burma, now known as Myanmar, responded by cutting its diplomatic ties with North Korea, and relations between the countries weren’t restored until 2007. The costly experience of three decades ago might have ensured North Korea would use borrowed hands for the alleged assassination in Malaysia, which is one of its few diplomatic partners, Koh said.