Israel's Prime Minister Benjamin Netanyahu on Saturday accused Iran-backed Hezbollah of trying to assassinate him, with the Middle East already on edge after Israel had vowed retaliation for an Iranian missile barrage.

An official in Gaza said an Israeli strike in north Gaza had killed at least 73 people late Saturday, with many more feared trapped under the rubble. Israel said it had hit a "Hamas terror target".

Netanyahu's office said a drone was launched towards his residence in the central town of Caesarea but he and his wife were not home and there were no injuries.

Rafael Nadal admitted his fitness level was well off the tour's top players after falling Thursday in straight sets to fellow Spaniard Carlos Alcaraz, who described the exhibition match as "a little bit sad".

The 38-year-old Nadal, who announced last week he would retire from tennis after the Davis Cup Finals in Malaga next month, lost 6-3, 6-3 to 21-year-old Alcaraz in the semi-finals of the "Six Kings Slam" event in Saudi Arabia.

The killing on Thursday of Hamas leader Yahya Sinwar spurred renewed calls for the release of scores of Israelis held hostage by the Palestinian militant group in Gaza.

As world leaders urged Hamas to release the hostages, their families and supporters voiced optimism that the killing of the mastermind of the October 7 attacks could give fresh life to talks on the hostages' release.

But despite the death of a leader widely seen as taking a hardline stance in negotiations for a hostage deal, analysts warned of the danger from a power vacuum left in his wake.

In a day marked by the death of Hamas leader Yahya Sinwar, displacement and more air strikes, exhausted Gazans said they just wanted to end more than a year of conflict that has brought untold suffering.

As news of Sinwar's death spread on cell phones, the first images of his corpse buried in rubble with a gaping hole in his head quickly emerged online.

The brutal images marked a dramatic end for the Gaza native who emerged as leader of the Palestinian group after igniting a war that has engulfed the region and ultimately sealed his own fate.

US President Joe Biden and the leaders of Germany, France and Britain pledged Friday to keep up support for Ukraine and condemned "Russia's continued war of aggression".

After meeting in Berlin, the four leaders in a joint statement "reiterated their resolve to continue supporting Ukraine in its efforts to secure a just and lasting peace".

Biden, Chancellor Olaf Scholz, President Emmanuel Macron and Prime Minister Keir Starmer said they had "discussed their plans to provide Ukraine with additional security, economic and humanitarian assistance".

Israel has inflicted an immense blow on Hamas by killing the Palestinian group's chief Yahya Sinwar, but whether his death will bring the end of the Gaza war any closer is unclear.

Israel had been hunting Sinwar since the October 7, 2023 attacks that he masterminded. Israeli leaders called the 61-year-old a "dead man walking".

Coming soon after the killing attributed to Israel of Hamas political leader Ismail Haniyeh in Tehran, Sinwar's death leaves Hamas facing a leadership vacuum and a strategy dilemma.

US President Joe Biden on Thursday hailed Israel's killing of Hamas leader Yahya Sinwar as a "good day" for the world, saying it removed a key obstacle to a Gaza ceasefire and hostage deal.

Vice President Kamala Harris, the Democratic presidential nominee in November's US election, added that Israel's killing of the mastermind of the October 7, 2023 attacks was a chance to "finally end the war in Gaza."

The Israeli military on Thursday told how Hamas leader Yahya Sinwar was killed in a firefight after being tracked "going from home to home" desperately seeking to avoid detection in southern Gaza.

Israel has hailed the death of the 61-year-old Sinwar as one of the most important blows it has dealt Hamas since the Gaza war started with the group's October 7, 2023 attacks.

After a career in the shadows, spent in Israeli prisons and the internal security apparatus of Hamas, Yahya Sinwar emerged as the leader of the Palestinian group after igniting a war that has engulfed the region.

Chief architect of the October 7, 2023 attack on Israel, the deadliest in its history, Sinwar was killed during an operation in Gaza, Israel's military said on Thursday.

Hamas has yet to confirm his death.

Some 345,000 Gazans face "catastrophic" levels of hunger this winter due to falling aid deliveries, UN agencies said Thursday, warning of the persistent risk of famine across the Palestinian territory.

This is up from the 133,000 people currently categorised as experiencing "catastrophic food insecurity", according to a classification compiled by UN agencies and NGOs.