New findings suggesting Yasser Arafat might have been poisoned have aggravated decades-old tensions between Palestinian rivals and with Israel that had long bedevilled the iconic leader.
Gaza's rulers Hamas and the Western-backed Palestinian Authority in the West Bank -- fiercely divided since 2007 -- quibbled over festivities commemorating Arafat nine years after his death.
And the findings by Swiss scientists, said to "moderately" support the idea he was poisoned with polonium, led to fresh accusations against Israel at a time when US-brokered peace talks seem once again on the verge of collapse.
"Sometimes, (leaders) who have died have more presence and influence that those in power who are still living," said an editorial in London-based pan-Arab daily Al-Sharq al-Awsat on Saturday.
"Arafat ... is capable, from his grave, of kicking up much dust at crucial, sensitive moments," it said.
On Monday Hamas forbade commemorations of Arafat, accusing its rival of trying to organise "only a Fatah ceremony" in the Gaza Strip and excluding the territory's Islamist rulers.
A heavy police presence saw an AFP correspondent briefly detained just for interviewing residents on the occasion.
Hamas called last week for end to peace talks and "concrete measures to find out who was involved in the crime" of Arafat's death.
Tawfiq Tirawi, head of the Palestinian Authority's inquiry into the death, hit back, saying: "If Hamas really cared about the death of Abu Ammar (Arafat's nom de guerre), they would allow festivities to go ahead in Gaza."
The fresh evidence that Arafat was poisoned has also cast a shadow over the ever-fragile Israeli-Palestinian peace process, just three months after it began.
Swiss lab results that were first published Wednesday by the Qatar-based satellite channel Al-Jazeera "moderately support the proposition that the death was the consequence of poisoning with polonium-210."
Since Arafat's death, Palestinians have given increasing currency to the rumour that he was murdered, with Israel the party most often blamed.
But there has never been any proof.
With the publication of the Swiss report, Palestinian officials said there was no longer any doubt, and demanded a formal international inquiry into who was responsible.
"Israel is the one and only suspect in the case of Yasser Arafat's assassination," Tirawi said Thursday.
On Monday, Arafat's nephew Nasser al-Qidwa urged the top Palestinian leadership to officially blame Israel.
"What's needed now is not more scientific evidence, but a clear political stance (by the Palestinian Authority) condemning and holding Israel responsible," he told a news conference in Ramallah.
Israeli officials have brushed the issue aside, categorically denying any involvement in Arafat's death.
The pan-Arab daily Al-Quds al-Arabi meanwhile reflected on how, nearly a decade on, the deeply polarising Arafat remains an icon of the Palestinian struggle for an independent state.
"Nine years after the assassination of Arafat, whom Israel considered an obstacle on the path to peace, nothing has changed on the ground, and it's high time Israel understood that no Palestinian will abandon the nationalistic principles Arafat stood for," the paper wrote on Thursday.
The latest talks have been on shaky ground, with Israel stepping up settlement construction on land the Palestinians want for their future state, angering negotiators.
Kerry delivered a grim warning to Israel on Thursday that failed negotiations with the Palestinians could trigger a new, bloody uprising.
Arafat shared a Nobel Peace Prize with Israeli leaders after signing the landmark Oslo accords in 1993, when hopes ran high for a negotiated settlement to the conflict.
But the negotiations broke down seven years later amid bitter recriminations on both sides, and a bloody Palestinian intifada, or uprising, erupted that would eventually claim the lives of some 3,000 Palestinians and 1,000 Israelis from 2000-2005.
Israel and the United States blamed Arafat for a wave of suicide bombings and other attacks on Israelis during the uprising, while Arafat insisted he was powerless to prevent Palestinians from retaliating for deadly Israeli military operations in the occupied territories.
Arafat, aged 75, died in Paris on November 11, 2004 after falling sick a month earlier while he was besieged by Israeli forces at his Ramallah compound. Doctors were unable to specify the cause of death and no post-mortem was carried out at the time.
In November 2012, his remains were exhumed and samples taken, partly to investigate whether he had been poisoned with polonium.
Some 60 samples were taken from Arafat's remains in November 2012 and divided between Swiss and Russian investigators and a French team carrying out a probe at the request of Arafat's widow.
The Russian investigation was inconclusive on the notion Arafat was poisoned, and the French have yet to reveal their results.