Forensic experts took samples from the body of former Palestinian president Yasser Arafat in Ramallah Tuesday, part of efforts by an international team investigating claims that he had died of poisoning.

The experts - from French, Swiss and Russian teams sent to the Palestinian city - did not remove the body. Rather, Toufik Tirawi, chairman of the Palestinian committee looking into Arafat's death, said they climbed into the crypt to take their samples.

The grave was then resealed, pending a small ceremony to take place later in the day.

The results of the tests are expected to be known by the end of the year at the latest.

Arafat died at the age of 75 in a French hospital on November 11, 2004. Medical records show he died of a brain hemorrhage, caused by a bowel infection. Some Palestinians blame Israel for his death, a claim Israel has strenuously denied.

An investigation by broadcaster Al Jazeera and a Swiss laboratory in July found unusual traces of polonium 210 on his clothes, raising fears of radioactive poisoning.

But Darcy Christen, the spokesman for the Institute of Radiology in Lausanne, told DPA at the time that the signs and symptoms described in Arafat's medical records were inconsistent with polonium poisoning, and stressed that the results were not sufficient to draw conclusions about the cause of death.

Polonium-210 is a rare radioactive element, many times more toxic than other poisons such as cyanide. Its most famous confirmed victim was Alexander Litvinenko, the Russian dissident and former spy who, according to a British inquiry, died in London in 2006 after polonium was dripped into his tea at a restaurant.

Roland Masse, a member of the prestigious Academie de Medecine, told the Times of Israel daily recently that Arafat had been tested for radiation poisoning, and the signs would have been "impossible to miss."

"A lethal level of polonium simply cannot go unnoticed," he said.

"When in contact with high levels of polonium, the body suffers from acute radiation, which translates into a state of anemia and a severe decrease in white blood cells. And yet Arafat did not present any of those symptoms. What did decrease was his platelets, not his white blood cells," he said.

Doctors said radioactive poisoning would normally cause victims to lose their hair, including eyebrows and lashes, within two to three days.

Litvinenko lost all his hair, while Arafat still had his white beard - longer even than his trademark three-day stubble - when he was helicoptered to the military hospital near Paris from his West Bank headquarters.