Hamas names Yahya Sinwar, mastermind of the Oct. 7 attacks, as its new leader in show of defiance

His selection is likely to provoke Israel, which has put him at the top of its kill list after the Oct. 7 attack, in which militants killed 1,200 people in southern Israel and took about 250 as hostages.

Hamas said in a statement it named Sinwar as the new head of its political bureau to replace Ismail Haniyeh, who was killed in Tehran last week in a blast Iran and Hamas blamed on Israel. Israel has not confirmed or denied responsibility. Also last week, Israel said it had confirmed the death of the head of Hamas' military wing, Mohammed Deif, in a July airstrike in Gaza. Hamas has not confirmed his death.

In reaction to the appointment, Israeli military spokesman Rear Adm. Daniel Hagari told Saudi-owned Al-Arabiya televsion, "There is only one place for Yahya Sinwar, and it is beside Mohammed Deif and the rest of the October 7th terrorists. That is the only place we're preparing and intending for him."

The two assassinations left Sinwar as the most prominent figure in Hamas. His selection signals that the leadership on the ground in Gaza — particularly the armed wing known as the Qassam Brigades — has taken over from the leadership in exile, which has traditionally maintained the position of the overall leadership to navigate relations with foreign allies and diplomacy.

Haniyeh, who had lived in self-imposed exile in Qatar since 2019, had played a direct role in negotiations over a cease-fire in Gaza through U.S., Qatari and Egyptian negotiators — though he and other Hamas officials always ran proposals and positions by Sinwar.

Speaking to Al-Jazeera television after the announcement, Hamas spokesman Osama Hamdan said Sinwar would continue the cease-fire negotiations.

"The problem in negotiations is not the change in Hamas," he said, blaming Israel and its ally the United States for the failure to seal a deal.

But he said Hamas "remains steadfast in the battlefield and in politics … The person leading today is the one who led the fighting for more than 305 days and is still steadfast in the field."

As Hamas' leader inside Gaza since 2017, Sinwar rarely appeared in public but kept an iron grip on Hamas' rule over the territory. Close to Deif and Qassam Brigades, he worked to build up the group's military capabilities.

He has been in deep hiding since the Oct. 7 attacks, which triggered Israel's campaign of bombardment and offensives aimed at destroying Hamas. The death toll among Palestinians is now nearing 40,000, most of the population of 2.3 million has been driven from their homes, and large swaths of Gaza's towns and cities have been destroyed. In May, prosecutors at the International Criminal Court sought an arrest warrant against Sinwar on charges of war crimes over the Oct. 7 attack, as well as against Israeli Prime Minister Benjamin Netanyahu and Israel's defense minister for war crimes.

Hugh Lovatt, an expert on the Israeli-Palestinian conflict at the European Council on Foreign Relations. said Israel's killing of multiple senior Hamas figures over the past months cleared the way for Sinwar. "Two weeks ago, few would have expected Sinwar to be the group's next leader despite the strong influence he exerts from Gaza," he said.

The killing of Haniyeh, a relative moderate, "not only opened the path for Sinwar to claim full control of Hamas, but also appears to have tipped the group into a more hardline direction," he said.