Diplomatic immunity hampers investigation into Kim Jong-nam's fatal poisoning

Malaysian police investigating the killing of North Korean leader Kim Jong-un's estranged half-brother believe they know somebody who might help them solve one of the most bizarre murder mysteries they have ever faced. They know his name, his nationality and have a pretty good idea where he's holed up.

The problem is he's a North Korean diplomat.

It's unusual for any country to simply hand over a diplomat, no matter the alleged crime. But for North Korea, in particular, the line between immunity and impunity can seem to be a pretty fine one.

Take the 2015 case of the first secretary of North Korea's embassy in Bangladesh, who was found to be carrying 170 undeclared gold bars worth an estimated $1.4 million. He was arrested but later released, with no charges filed, and left the country. The following year, another official at the same embassy was asked to leave after an attempt to smuggle a shipping container full of one million cigarettes and electronics worth another $1 million.

Last year, a report by the Global Initiative Against Transnational Organized Crime said a South Africa-based North Korean diplomat may have been involved in smuggling rhino horn but managed to evade charges.

Enter second secretary Hyon Kwang Song, the current person of interest. Malaysian police have released little information about him, except that he is 44 and arrived in Malaysia on Sept. 20.

7 wanted for questioning

Police investigating the poisoningof Kim Jong-nam in an airport shopping area on Feb. 13 are seeking seven North Korean nationals in connection with the case. Most have left the country, but authorities say they believe three remain diplomat Hyon; an employee of Air Koryo, the country's flag carrier; and a person named Ri Ji U.

It's not hard to imagine where they might be: the North Korean Embassy, a plain, yellow two-storey house in an affluent neighbourhood just 10 minutes from downtown. A large group of journalists and photographers has camped outside the embassy since news broke of Kim Jong-nam's killing.

Whether the people the police want to talk to are indeed at the embassy is anybody's guess. Police can't check because to do so they need permission from North Korea, which so far has declined.

National police Chief Khalid Abu Bakar said investigators have submitted a request through Malaysia's Foreign Ministry to the North Korean Embassy to interview Hyon.

"If you have nothing to hide, you do not have to be afraid," he said. "You should co-operate."

Diplomatic immunity

The Vienna Convention on Diplomatic Relations says a foreign diplomat is "inviolable" and is not liable to any form of arrest or detention. It also adds that "a diplomatic agent shall enjoy immunity from the criminal jurisdiction of the receiving state." That can only be waived by the diplomat's own government.

Due to allegations the North uses its embassies abroad to make money for its nuclear and missile programs, United Nations sanctions now call for vigilance against North Korean diplomats engaged in illicit activity.

Even so, few things are more established in the way the diplomatic community around the world conducts its day-to-day business than the concept of diplomatic immunity the essential freedom of diplomats to travel and conduct their duties without the fear of being arrested or harassed for political reasons.

When diplomatic immunity and the realities of a criminal investigation butt heads, local police tend to have the weaker hand.

And that doesn't bode well for Malaysian investigators hoping North Korea will open its doors.

"If he is a Korean diplomat with a diplomatic passport, then he has immunity no matter a criminal case or otherwise," lawyer Sankara Nair, who has handled several cases involving diplomats, told The Associated Press in Kuala Lumpur. "The police can apply any warrants they want but it can easily be set aside by the embassy."

South Korea alleges other executions

South Korea's spy agency raised other allegations about its neighbour to the north on Monday.

North Korea executed five senior security officials with anti-aircraft guns because they made false reports that "enraged" leader Kim Jong-un, the agency said.

The comments by the National Intelligence Service were raised in a private briefing with Malaysialawmakers investigatingKim Jong-nam's killing. South Korea said it believes Kim Jong-un ordered the assassination of his sibling.

• V for venom: 6 questions about nerve agent used in Kim Jong-nam death

The spy agency alleges that five North Korean officials in the department of recently purged state security chief Kim Won-hong were executed because of the false reports to Kim, South Korean lawmaker Lee Cheol-woo said. It's not clear what false reports they allegedly made, and the intelligence service didn't say how it got its information.

South Korean spies have a spotty record when reporting about high-level events in authoritarian, cloistered North Korea.

North Korea fired Kim Won-hong in January, presumably over corruption, abuse of power and torture committed by his agency, Seoul said earlier this month. The fallen minister had been seen as close to Kim Jong-un. North Korea has not publicly said anything about Kim Won-hong or about the alleged executions of people who worked for him.

Lee also cited the intelligence service as saying that Kim Won-hong's dismissal was linked to those false reports, which "enraged" Kim Jong-un when they were discovered.

Since taking power in late 2011, Kim Jong-un has reportedly executed or purged a large number of high-level government officials in what rival Seoul has called a "reign of terror."

• The world according to Kim: Inside North Korea's efforts to keep everyone out

What it means for the U.S.

U.S. officials huddled Monday with key Asian powers to discuss tensions with North Korea, which have been stoked by the airport killing and a recent missile test.

North Korea's rapid progress toward acquiring a nuclear-tipped missile that could strike the U.S. mainland poses one of the sternest national security challenges for President Donald Trump, whose administration is currently conducting a policy review on how to deal with the communist government.

On Monday, U.S. special representative for North Korea policy Joseph Yun huddled at the State Department with his Japanese and South Korean counterparts, Kenji Kanasugi and Kim Hong-kyun. The meeting was part of continued U.S. efforts to get its main allies in Asia to co-operate more closely on security.