Tawhiq al-Tirawi Ramallah - Sona Adeek      Tawhiq al-Tirawi, head of the Palestinian Authority\'s official investigation committee recently assigned to investigate the death of Yasser Arafat, has revealed that the historic Palestinian leader\'s latest blood sample, taken before his medical treatment, is missing. The committee is reportedly searching for the sample in al-Moqataa, the headquarters of the Palestinian presidency in Ramallah. Arafat, a Nobel Peace Prize winner who led the struggle for Palestinian statehood for nearly four decades, died on November 11, 2004, following several weeks of treatment. Rumours have swirled around the circumstances surrounding Arafat\'s death, after an investigation carried out by the Qatari news channel Al Jazeera showed that the leader may have been poisoned by polonium, a radioactive element. Tirawi said the missing sample was sent to Jordan by Arafat\'s physician, Dr Ashraf al-Kurdi, before it was lost. In an exclusive interview with Arabstoday, Tirawi said he knew that Arafat would never return to Palestine when he boarded the plane to a French hospital, to get treated for an unidentified ailment he suffered from in his last days. \"I said this to [the Palestinian chief negotiator] Saeb Erakat and [the Arab MP in Israel\'s Knesset] Ahmed el-Tayibi, when Arafat boarded the plan; Israel wouldn\'t let him return even if he was to recover from his illness,\" said Tirawi. On researching Arafat\'s belongings to find any traces of polonium, Tirawi said his committee has information that the Palestinian freedom fighter\'s close friend Emad Abu Zaki retained a few of the late leader\'s belongings, including clothes, shoes, a military uniform and traditional scarves. The investigating committee is reportedly in talks with Abu Zaki to send these belongings be tested in advanced laboratories. Laboratory research carried out in Switzerland and cited in an Al-Jazeera report on Tuesday said polonium poisoning may have caused Arafat\'s death in 2004. The Fatah founder\'s widow, Suha Arafat, said then that the Palestinian, Arab and Muslim nations, now have the right to know the truth about the \"matryrdom\" of her deceased husband, nicknamed Abu Ammar. \"I confirm that [the late] President Arafat was poisoned...the scientific examination will push the public to act pressure officials to track the killers and whoever stands behind them,\" said Suha Arafat in an exclusive statement to Arabstoday. \"Me, my daughter Zahwa, my family and all the Palestinian people, whom Arafat has dedicated his life for, will do everything possible to catch the killers,\" she added. The Swiss laboratory\'s analysis focused on biological samples taken from Yasser Arafat\'s belongings –- including his clothes, his toothbrush, even his iconic koffiyeh (Palestinian traditional scarf) -– given to his wife by the military hospital in Paris where he died, according to Francois Bochud, head of the Institute of Radiation Physics at the University of Lausanne. Doctors did not find any traces of common heavy metals or conventional poisons, so they turned their attention to more obscure elements, including polonium. \"The conclusion was that we did find some significant polonium that was present in these samples,\" Bochud told Al-Jazeera. Tirawi said that PA officials suspected Arafat was poisoned before his death, which is why they searched for the best place capable of finding poison traces. They were then recommended to try France. \"The French hospital said then that there were no traces of any poison in Arafat\'s body, and that\'s makes us wonder if they don\'t know about polonium in France, despite the fact that they have nuclear reactors there? Now we can understand that the French preferred to distance themselves from this issue, but we have to ask them whether they searched for radiation poison in Arafat\'s body or not. And whether they knew about it, but probably hid the story...or did they actually found nothing suspicious?\" he added. Doctors in Lausanne had hoped to study the blood and urine samples taken from Arafat while he was at Percy Military Hospital in France. But when she requested access, the hospital told his widow that those samples had been destroyed. “I was not satisfied with that answer,” said Suha Arafat. “Usually, for a very important person, like Yasser, they would keep traces – maybe they don’t want to be involved in it?” PA official Tirawi also played down accusations directed at the PA of being involved in the plot that led to Arafat\'s death. \"These accusations are ridiculous, the PA can\'t be accused of treason that easilt. However, whoever has evidence about such allegations can go to the prosecution or even to the press,\" he said. On the work of his committee, Tirawi said it was only assigned to hold legal investigations with whoever had information about the case, but medical issues were handed to specialists. However, he revealed to Arabstoday that the committee had significant results which will be announced to the Palestinians and the entire world. Tirawi dismissed a documentary aired by al-Mayadeen channel, in which a young Palestinian man alleged he had information that could lead to reveal the truth about Arafat\'s death. \"This man\'s words look illogical, I believe there are attempts to create a state of uncertainty about Arafat\'s death, and this could be one of those attempts,\" he finished.     Polonium is a highly radioactive element used, among other things, to power spacecraft. Marie Curie discovered it in 1898, and her daughter Irene was among the first people it killed: She died of leukemia several years after an accidental polonium exposure in her laboratory. It was also used to kill Russian former spy turned Kremlin critic Alexander Litvinenko, who died in 2006 after drinking tea laced with the radioactive substance at a London hotel. He had been airlifted to France from his besieged headquarters in the Israeli-occupied West Bank. French officials, citing privacy laws, refused to reveal the precise cause of death or the nature of his condition, fuelling a host of rumours and theories as to the cause of his illness. Theories went from cancer, cirrhosis of the liver, to even allegations that he was infected with HIV. At the time of his death at the age of 75, Palestinian officials charged he had been poisoned by longtime foe Israel, but an inconclusive Palestinian investigation in 2005 ruled out cancer, AIDS or poisoning. Suha Arafat has reportedly asked the PA to exhume her late husband’s body from its grave in Ramallah.   A conclusive finding that Arafat was poisoned with polonium would not, of course, explain who killed him. It is a difficult element to produce, though – it requires a nuclear reactor – and the signature of the polonium in Arafat’s bones could provide some insight about its origin.