According to a report from Swiss scientists, Yasser Arafat's remains contained 18 times the normal levels of polonium-210, adding to already widespread-speculation that the former Palestinian leader was assassinated. The scientists said they were "83 percent" sure Arafat was poisoned with the radioactive metal.

"Yasser Arafat died of polonium poisoning," Dave Barclay, a UK forensic scientist told Al Jazeera. "We found the smoking gun that caused his death. What we don't know is who's holding the gun at the time."

"The level of polonium in Yasser Arafat's rib…is about 900 milibecquerels," Barclay added. "That is either 18 or 36 times the average, depending on the literature."

The 108-page report, first published in Al Jazeera, was based on samples obtained after Arafat's body was exhumed last November. A French team of forensic experts are also investigating the samples as part of a murder investigation, as are a Russian team working on behalf of the Palestinian Authority.

Polonium-210 is a highly radioactive metal that is harmless to humans as long as it isn't ingested or otherwise absorbed into the bloodstream; if it is, exposure to a speck-sized amount could prove fatal. It's been used in several high-profile assassinations, most recently the 2006 poisoning of former KGB officer Alexander Litvinenko.

Arafat's death has long been the subject of assassination theories, in part because, when he died in November 2004, doctors at Percy Hospital in Paris did not perform an autopsy or release an official cause of death. One month before his transfer to Percy, during the second intifada, Arafat had fallen suddenly ill while eating dinner his compound in Ramallah, despite being in good health beforehand, according to the Swiss report.

"It is scientifically proved that he didn't die a natural death, and we have scientific proof that this man was killed." Arafat's widow, Suha, said, though she stopped short of blaming a specific party or country. "We can't point a finger at anyone, the French are conducting a serious investigation. It takes time."

[Image via AP]