Hamas leader Yahya Sinwar was killed in combat, Khalil Al-Hayya, deputy Gaza Hamas chief and the group's chief negotiator, said on Friday.
Sinwar's death, which follows Israeli assassinations of other Hamas leaders and commanders, will deal a huge blow to the group which has faced relentless air strikes since it attacked Israel on October 7, 2023, killing 1,200 people, according to Israeli tallies.
It also dragged about 250 people back to Gaza, creating a hostage crisis for Israeli Prime Minister Benjamin Netanyahu's far-right government which has vowed to eliminate Hamas.
Sinwar was named the group's paramount leader on August 6, as a successor to former political chief Ismail Haniyeh, who was assassinated in Tehran on July 31.
Widely known as the architect of the October 7, 2023 attack, Sinwar has been in Gaza, defying Israeli attempts to kill him since the start of the war.
Born in a refugee camp in the southern Gaza city of Khan Younis, Sinwar, 62, was elected as Hamas' leader in Gaza in 2017.
The controversial leader, who spent half his adult life in Israeli prisons, was the most powerful Hamas leader left alive following the assassination of Haniyeh.
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