Former Palestinian leader Yasser Arafat may have been poisoned to death with radioactive polonium, scientists in Switzerland have revealed.

Arafat died in France on November 11, 2004, at the age of 75, but at the time doctors were unable to specify the cause of death.

Experts revealed that several belongings and items of clothing belonging to Arafat, including his toothbrush, hat and underwear, contained high ‘unexplained levels’ of the radioactive material.

Arafat, who died after falling ill at his headquarters in the West Bank, showed symptoms of nausea, stomach pain and kidney and liver failure – signs consistent with radiation poisoning.

But the lack of hair loss or a shortage of bone marrow casts doubt on that theory, the scientists admit.

Much rumour had surrounded Arafat’s death after doctors couldn’t identify how he died.

Speculation continued unabated when his widow Suha initially refused a post mortem examination on her husband’s body.

But she changed her mind and asked judges in France last year to launch a murder probe into her husband’s death, claiming he was poisoned because he was an ‘obstacle to peace’.

Experts at Lausanne’s Radiation Physics Institute have now released details of the tests which ‘support the possibility’ he did not die of natural causes.

A statement said: ‘Several tests on samples of bodily fluids contained an unexplained higher level of polonium 210, compared to control samples.

‘These findings support the possibility of Arafat’s poisoning with polonium 210.’

The team, whose findings are published in British medical journal The Lancet this week, said they regretted that no post-mortem investigation was carried out after Arafat’s death.

Polonium breaks down quickly in the human body and is difficult to trace if there is a delay.