More than two years after accusations arose that Palestinian leader Yasser Arafat's 2004 death was the result of polonium-210 poisoning, French judges say there isn't enough evidence to support the claim that Arafat was murdered.

"At the end of the investigation ... it has not been demonstrated that Mr Yasser Arafat was murdered by polonium-210 poisoning," the judges said, according to France 24.

When Arafat died in France in November 2004, doctors said he had suffered a stroke. But his widow, Suha, did not agree. And in 2012, she filed a murder case, after traces of polonium-210 were found on Arafat's belongings.

Arafat's burial site was then opened, to allow investigators to test samples from his body. And in November 2013, "the Swiss team that tested Arafat's remains said they found evidence to "moderately support" the polonium-210 theory, as the Two-Way reported.

Polonium-210 is a reactive element that became well-known after it was blamed in the poisoning death of Alexander Litvinenko, a former KGB agent who criticized Russia and who died in London in 2006.

As poison expert Deborah Blum told NPR back in 2012, the evidence in the Arafat case is complicated by the fact that the former Palestinian leader was a heavy smoker.

"Cigarette smoke is quite remarkably loaded with polonium-210," Blum said, describing a situation that stems from fertilizers used to grow tobacco.

Blum also said:

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