N. Korea's art of brinkmanship

North Korean ambassador to Malaysia Kang Chol, who is expelled from Malaysia, arrives at Kuala Lumpur international airport in Sepang, Malaysia March 6, 2017.

Pyongyang's travel ban on Malaysians leaving North Korea sharply escalated the already-high tensions with Kuala Lumpur - but is only the latest episode of the isolated country's diplomatic brinkmanship.

The authoritarian, nuclear-armed state has a long history of using foreigners - especially American tourists or missionaries - as bargaining chips in its nuclear and aid negotiations with the US.

The reclusive nation has also occasionally shut its borders in the face of external health threats, or in protest at times of military tension with the South, despite the potential consequences.

Here are some of its most notable measures: .

Read also: Malaysia says North Koreans not allowed to leave: Deputy PM

A number of Americans have been arrested and jailed for crimes including hostile acts and illegal religious activity, sometimes for years.

Many were released after visits by high-profile US figures including ex-presidents Jimmy Carter and Bill Clinton, but with relations between Pyongyang and Washington in the deep freeze two remain in the North.

Otto Warmbier, a 22-year-old college student, was last year sentenced to 15 years' hard labour for stealing propaganda materials. Kim Dong-Chul, a Korean-American pastor, has been jailed on spying charges.

The North receives a tiny number of overseas visitors, but closed its borders to foreign tourists for more than four months from October 2014 in a bid to keep out the Ebola virus - when no cases had been reported in Asia.

It went so far as to enforce a 21-day quarantine period on anyone entering the country, including foreign diplomats and businessmen.

Read also: Malaysian PM Najib calls on North Korea to release all Malaysians

Tourism is a crucial source of hard currency for the impoverished nation, but the country, notorious for weak medical infrastructure and chronic lack of medicines, appeared willing to take a financial hit.

When South Korea suffered from the world's largest outbreak of Middle East Respiratory Syndrome, or MERS, in summer 2015, the North reportedly prohibited its diplomats and workers overseas from returning to their homeland for months to prevent the spread of the virus.

Pyongyang also suspended foreign tours for three months due to fears over SARS in 2003.

Read also: PM Najib to N. Korea: Release our people

The Kaesong industrial complex - where more than 100 South Korean firms employed over 50,000 North Korean staff in a reconciliation project - suffered several political setbacks after it was set up in 2004, eventually closing in 2016.

Pyongyang abruptly withdrew all its workers in April 2013 in protest at joint military exercises between Seoul and Washington, and ordered all South Korean managers to leave immediately.

Most South Koreans managed to depart, but seven were ordered to stay until remaining wages for North Korean workers were paid, stoking fears that they would be held as hostages.

Half-brother of N Korean leader assassinated in Malaysia

  • Doan Thi Huong, 28, from Vietnam, was surrounded by a heavy police presence as they were charged in a Kuala Lumpur court over the killing.
  • Indonesian Siti Aisyah, 25, was surrounded by a heavy police presence as they were charged in a Kuala Lumpur court over the killing.
  • Huong, also dressed casually, then heard the charge in Vietnamese.
  • Siti, wearing a red T-shirt, was brought in first to hear the murder charge read out before being taken away.
  • The handcuffed women were both told they faced the death penalty if found guilty.
  • Neither woman was asked to enter a plea and their trial is not expected to begin for several months.
  • Four suspects in the Kim Jong Nam murder: Malaysian Muhammad Farid Bin Jalaluddin (top L), Doan Thi Huong (top R) of Vietnam, North Korean Ri Jong Chol (bottom L) and Siti Aisyah of Indonesia (bottom R).
  • : A still image from a footage broadcast by Chinese state media which they say is believed to show the second woman (wearing yellow top) suspected of involvement in the apparent assassination of Kim Jong Nam.
  • Mystery woman: A CCTV screen grab showing a woman outside what looked like the airport, was circulated briefly after news broke last night that the half-brother of North Korean leader Kim Jong-un had been killed in Malaysia. The picture fits the description of one of the two women believed to be North Korean spies, who had poisoned Kim Jong-nam during a brazen attack at KLIA2.
  • CCTV cameras at KLIA2 have captured a clearer image of a woman believed to be one of the assassins who killed Kim Jong-nam, the half-brother of North Korean leader Kim Jong-un.
  • The image zooms in on the alleged killer's features, depicting her to be middle-aged and of Asian descent.
  • In the grainy image, she can be seen wearing a top with the word "LOL" in large letters and a blue short skirt, with her right hand over a small sling handbag.
  • North Korea embassy officials leave the morgue at Kuala Lumpur General Hospital where Kim Jong Nam's body is held for autopsy in Malaysia.
  • Jong-nam, 45, died after he was attacked at the Kuala Lumpur International Airport 2 (KLIA2) on Monday.
  • He is believed to have been attacked by two female agents who splashed his face with a chemical at the airport's departure hall at about 9am on Monday.
  • A statement confirming the death from the Royal Malaysia Police force.
  • Three cars belonging to the North Korean embassy were seen in the compound of the mortuary at Kuala Lumpur Hospital (HKL). At least two of the cars were parked inside the compound while the third was seen parked outside with a police patrol car parked behind it. The cars had diplomatic number plates, one of which was 28-35-DC.
  • Occupants of the cars were at the mortuary where a post-mortem on the body of Kim Jong-nam, the half-brother of North Korean leader Kim Jong-un, was being carried out.
  • North Korean female agents operating in Malaysia have reportedly assassinated the half-brother of the North's leader, Kim Jong-Un - a one-time heir apparent who became a critic of the Stalinist regime.
  • South Korean media said Tuesday that Kim Jong-Nam was killed with poisoned needles at Kuala Lumpur International Airport. Officials in Seoul and the Malaysian capital could not confirm his death.
  • Malaysian police said in a statement late Tuesday that a North Korean man, identified as Kim Chol, sought medical assistance at the airport and died on the way to hospital.
  • South Korean media said Jong-Nam had travelled using a fake passport under the name of Kim Chol.
  • If confirmed, it would be the highest-profile death under the Jong-Un regime since the execution of the leader's uncle, Jang Song-Thaek, in December 2013.
  • Jong-Un has been trying to strengthen his grip on power in the face of growing international pressure over his country's nuclear and missile programmes. He has reportedly staged a series of executions. 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.
  • 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.
  • Malaysian private security guards stand guard outside the Forensics department at Putrajaya Hospital in Putrajaya on February 14, 2017, where the body of a North Korean man suspected to be Kim Jong-Nam, half-brother of North Korean leader Kim Jong-Un is believed to be kept.
  • The 45-year-old was killed by two unidentified females wielding poisoned needles at the airport, according to South Korean broadcaster TV Chosun.
  • It said the women hailed a cab and fled immediately afterwards. Jong-Nam, the eldest son of former leader Kim Jong-Il, was once seen as heir apparent but fell out of favour following an embarrassing botched attempt in 2001 to enter Japan on a forged passport and visit Disneyland. He has since lived in virtual exile, mainly in the Chinese territory of Macau.
  • A pedestrian walks in front of a clinic where a North Korean man suspected to be Kim Jong-Nam, half-brother of North Korean leader Kim Jong-Un is believed had been taken at Kuala Lumpur International Airport 2 (KLIA 2) in Sepang, outside Kuala Lumpur on February 14, 2017.
  • His half-brother took over as leader when their father died in December 2011. Jong-Nam, known as an advocate of reform in the North, once told a Japanese newspaper that he opposed his country's dynastic system of power.
  • He was reportedly close to his uncle Song-Thaek, once the North's unofficial number two and political mentor of the current leader. 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.
  • Policemen stand outside the morgue at Putrajaya hospital in Malaysia February 15, 2017.
  • In 2014, Jong-Nam was reported to be in Indonesia - sighted at an Italian restaurant in Jakarta - and was said to be shuttling back and forth between Singapore, Indonesia, Malaysia and France.
  • N Korean officials scuffle with media outside the KL hospital.
  • N Korean officials speaking to Malaysian authorities.
  • The Korean restaurant along Tanjong Pagar road where Kim Jong Nam was said to have dined in when he was spotted in Singapore in 2014.

The group were eventually allowed to return home nearly a month later, after Seoul sent a convoy carrying more than $10 million in cash across the border.

The complex resumed operations in September 2013, but last year Seoul declared the project would shut down to punish Pyongyang for its nuclear and missile tests.

The North responded a day later by expelling all southern managers and freezing all South Korean assets in the zone.

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