Since ancient times, poisoning has been a favoured method of bumping off political adversaries, with historians still debating if Cleopatra, Napoleon and Alexander the Great were assassinated this way.
One of the most shocking recent cases was the 2017 assassination of Kim Jong Nam, the estranged half-brother of North Korea’s leader, who had toxic nerve agent VX smeared in his face as he waited for a flight at Kuala Lumpur airport.
On Friday Malaysian authorities freed a Vietnamese woman who stood trial over the murder after she accepted a reduced charge, weeks after her Indonesian co-accused was released, meaning there is no one left in custody over the killing.
The women claimed they were tricked into carrying out the murder by North Korean agents who fled after the killing.
The methods, toxin of choice and final result vary widely but here are five high-profile poisonings or attempted poisonings:
A retired Russian double agent, Sergei Skripal, was leading a seemingly peaceful life in the English cathedral city of Salisbury when he and his visiting daughter Yulia were targeted in a nerve agent attack.
They were discovered unconscious on a park bench in March last year after being poisoned by what investigators said was a highly toxic nerve agent, Novichok.
Britain accused the Russian government of trying to kill Skripal in retribution for his ongoing work with European intelligence agencies, a charge vehemently denied by Moscow.
London named two Russian nationals as suspects over the attack, and investigative group Bellingcat has said they were employees of Moscow’s GRU military intelligence service.
‘Toxic tea for three’
Another attack involving a former Russian agent happened in November 2006, when Alexander Litvinenko met two Russian contacts for tea at a top London hotel to discuss possible future business opportunities.
The 43-year-old fell ill immediately afterwards and was found to have drunk tea laced with Polonium-210 — a rare and expensive radioactive isotope produced in Russia.
He died after three agonising weeks and was eventually buried in north London in a lead-lined coffin to prevent radiation leakage.
A British inquiry found that Russian President Vladimir Putin had “probably approved” the ex-spy’s murder, a finding dismissed by Moscow as a “joke”.
Litvinenko’s killing caused widespread public outrage in Britain after radioactive traces were found at various sites around London, with media dubbing it the world’s first act of “nuclear terrorism”.
Bulgarian with a brolly
In 1978, at the height of the Cold War, Bulgarian dissident Georgi Markov was waiting for a bus home after a shift at the BBC World Service.
He felt a sharp jab in his thigh and turned to see a man picking up an umbrella. Three days later, Markov was dead, killed by what many believe to have been a poisoned dart filled with ricin and fired from the brolly.
A post-mortem examination established he had been killed by a tiny pellet containing a 0.2-milligram dose of ricin.
Ricin is 6,000 times more powerful than cyanide and a speck no bigger than a grain of salt is enough for fatal results.
The case has never been solved.
Viktor Yushchenko would go on to be president of Ukraine but in September 2004, he was engaged in a bruising election campaign battle against pro-Moscow candidate Viktor Yanukovich when he fell seriously ill.
Months of tests in an Austrian clinic determined that he had ingested a massive amount of dioxin, with the doctor who treated him saying the levels in his body were 1,000 times higher than normal.
Although he survived, Yushchenko’s face was left bloated and pockmarked, and he had to undergo regular treatment in Switzerland to flush the toxin from his body.
He later claimed that he believed the dioxin had come from a Russian factory.
Posing as Canadian tourists, agents from Israeli secret service Mossad targeted Khaled Meshaal, the head of the Hamas political bureau, by injecting a mysterious poison into his ear on a street in Jordan’s capital Amman.
As Meshaal slipped into a coma, Jordanian police captured two of the attackers and a furious King Hussein demanded that Israel hand over an antidote if it wanted its agents back.
A red-faced Prime Minister Benjamin Netanyahu eventually provided the antidote and also released Hamas spiritual leader Sheikh Ahmad Yassin from an Israeli prison. – AFP