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The 62-year-old, who took over control of Hamas within Gaza in 2017, is believed to be the mastermind of the 7 October 2023 attacks.

Footage shot by an Israeli drone purports to show Sinwar - possibly wounded and missing his right hand - sitting in a chair on the upper floor of a ruined building just before his death.

The figure, who has their face covered, is seen staring at the drone before appearing to throw an object at it.

Israeli foreign minister Israel Katz said earlier officials could confirm Sinwar's death following DNA tests and other checks, like dental records, on a body found in rubble in Gaza.

He added that his death was a "great military and moral achievement for Israel".

"The elimination of Sinwar creates an opportunity for the immediate release of the hostages and a potential change that could lead to a new reality in Gaza - without Hamas and without Iranian control."

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It comes after photographs circulated online earlier claimed to show the Hamas leader's dead body.

Sky News has carried out verification checks on the image and we believe the body it shows does resemble Sinwar.

His death means Israel has eliminated its main target since it began strikes and ground invasions in Gaza in response to the Hamas incursion last year.

Following Israel's announcement, Prime Minister Keir Starmer said the UK "will not mourn his death".

He added: "The release of all hostages, an immediate ceasefire and an increase in humanitarian aid are long overdue so we can move towards a long-term, sustainable peace in the Middle East."

Meanwhile, US President Joe Biden welcomed the news, saying it was "a good day for Israel, for the United States, and for the world."

In a statement, he compared the killing to that of Osama bin Laden, adding it "proves once again that no terrorists anywhere in the world can escape justice, no matter how long it takes".

Before announcing it had confirmed Sinwar's death, the Israeli military said in a statement: "During IDF operations in Gaza, three terrorists were eliminated...

"In the building where the terrorists were eliminated, there were no signs of hostages in the area. The forces that are operating in the area are continuing to operate with required caution."

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Hamas has not yet officially commented on the reports, but sources from the group, quoted by Reuters news agency, said there were indications he had been killed.

US officials previously told Sky News' US partner NBC News that the Israeli mission seemed to have been carried out on Wednesday, possibly in Rafah.

They added that the US had not been involved and did not provide intelligence, with senior Pentagon officials only finding out after the operation had been carried out.

US sources said they believed the killing of Sinwar had been a "lucky break" for the Israeli military, NBC also reported.

Sinwar took over full leadership of Hamas after the killing of Ismail Haniyeh, who was the political leader of the group, in Iran in July.

He was believed to have been hiding in the network of tunnels beneath Gaza since the militant group's attack on Israel last year.

It comes as Israeli forces continued a more than week-old major air and ground assault in the Jabaliya refugee camp in northern Gaza.

An Israeli strike hit a school sheltering displaced Palestinians on Thursday, killing at least 28 people, including five children, according to Gaza's health ministry.

The war in Gaza is now more than a year old - with Israel having killed more than 42,000 Palestinians in response to Hamas's incursion on 7 October last year, according to the Gaza health ministry.

Hamas killed some 1,200 people and captured around 250 hostages when its militants entered Israel on 7 October.