He was the younger brother of Yahya Sinwar, the former Hamas leader killed by Israel last year. Hamas did not immediately respond to the claim of his death.

Izz al-Din al-Haddad is poised to become Hamas's new leader after Muhammad Sinwar's death in an Israeli airstrike. As the most senior surviving commander from Hamas's pre-war Gaza leadership, al-Haddad is expected to assume operational control.

Mohammad Sinwar, Hamas's Gaza leader and brother of slain commander Yahya Sinwar, has been confirmed dead by Israeli Prime Minister Benjamin Netanyahu.