Scientists in Switzerland claim to have found traces of polonium in the effects of the late Palestinian leader Yasser Arafat.
Test results presented in a television documentary for Al Jazeera showed his clothes, toothbrush and headscarf exhibited surprisingly high levels of the poisonous element.
Arafat’s widow has called for her late husband’s body to be exhumed.
Arafat initially led the Palestinian Liberation Organisation’s fight against Israel but went on to sign a peace agreement establishing Palestinian self-rule in the West Bank and Gaza.
He died in a hospital in France in 2004 after a sudden illness which baffled doctors fuelling numerous rumours and theories.
In 2006 Polonium was found to have caused the death of former Russian spy Alexander Litvinenko in London – he was assumed to have been deliberately poisoned.