It added that Haddad had held Israeli hostages during the war and had surrounded himself with them to protect his life.

Hamas officials separately confirmed the killing, saying Haddad died in an attack on a residential building.

Mosques in northern Gaza also announced Haddad’s “martyrdom”. His funeral was held in Gaza City, where mourners carried his body, wrapped in Hamas and Palestinian flags.

Benjamin Netanyahu, the Israeli Prime Minister, described Haddad as “one of the architects” of the October 7 attack.

He pledged to continue pursuing those involved in the massacres, saying: “Sooner or later, Israel will reach you”.

Despite the warring parties agreeing to a ceasefire last October, Gaza has seen near-daily exchanges of fire that have killed more than 850 people, according to the Gaza Health Ministry.

In the north, the Israeli military has continued to strike Hezbollah targets in Lebanon even as Israel and Beirut agreed in Washington to extend a ceasefire by 45 days.

“The April 16 cessation of hostilities will be extended by 45 days to enable further progress,” a United States State Department official said.

The official said the two sides would meet in July for talks aimed at reaching a permanent peace deal.

Lebanon’s delegation at the talks in Washington said that the extension of the ceasefire agreement, alongside the creation of a US-backed security mechanism, could help lay the groundwork for “lasting stability” in the region.

The Israeli military said its forces had killed more than 220 Hezbollah fighters in southern Lebanon over the past week.

It added that Israeli troops had also carried out strikes on more than 440 Hezbollah targets in the area during that period.