The Palestinian mastermind of the Achille Laurocruise ship hijacking in 1985 has died of natural causes in US custody in Iraq.
"Mohammed Abbas or Abu Abbas, head of the Palestine Liberation Front (PLF), who has been held in American custody, has died in Iraq," an official close to President Yasser Arafat said.
A US official said Abbas, caught by US forces in April, apparently died of a heart attack.
Mr Omar Sheble of the Palestinian Liberation Front (PLF), accused the US of "assassinating" Abbas. "They put him to die slowly in a prison cell, deprived of his freedom. His detention was illegal and his conditions in jail were bad."
Abbas planned the hijacking of the Italian cruise liner Achille Lauroin October 1985 during which a wheel-chair bound American Jew, 69-year-old Leon Klinghoffer, was killed and thrown into the sea.
Abbas, who was not on board the ship during the attack spent most of the past 17 years in Iraq, eluding US and Italian officials. He was believed to be in his late 50s or early 60s.
Italy had released Abbas after US warplanes intercepted his jet and forced it to land in Italy shortly after the Achille Laurohijacking. But it tried Abbas and sentenced him to five life terms in prison after he had already left the country.
Washington dropped a warrant for Abbas's arrest several years ago and Israel declared him immune from prosecution over the hijacking in 1999 after he was allowed to return to Gaza by officials who concluded he was no longer involved in militancy.