The 62-year-old, who has led Hamas within Gaza since 2017, is believed to be the mastermind of the 7 October 2023 attacks.
Israeli foreign minister Israel Katz made the claim following DNA tests and other checks, like dental records, on a body found in Gaza.
He said officials could now confirm Sinwar was “killed today by IDF [Israeli Defence Forces] soldiers”.
Mr Katz 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.”
It comes after photographs circulated online earlier claimed to show Sinwar’s dead body.
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.
Before announcing it believed it had killed Sinwar, 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.”
This is a limited version of the story so unfortunately this content is not available.
Open the full version
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 believed that, assuming Israeli confirmation is correct, the killing of Sinwar was 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.
US President Joe Biden has been briefed and US officials have been in close contact with Israeli officials throughout Thursday, according to a senior administration official.
