Hamas chief Ismail Haniyeh said Wednesday three of his sons and four grandchildren were killed in an Israeli strike in Gaza, where war has raged for more than six months.

The Qatar-based political head of the Palestinian group confirmed to Al Jazeera "the martyrdom of my three sons and some of my grandchildren".

According to Al Jazeera, a drone hit the family's car in the northern Gaza Strip's Al-Shati refugee camp.

Speaking from a Doha hospital where he was told of the strike, Haniyeh was defiant.

He argued that by targeting relatives of Hamas leaders, "the (Israeli) occupation believes... it will break the determination of our people".

But, according to Haniyeh, such actions would fail to force Hamas's hand in negotiations towards a truce and hostage release.

"All our people and all the families of Gaza have paid a heavy price in blood, and I am one of them," Haniyeh added.

He told Al Jazeera that now nearly "60 members of my family have been martyred, including my grandchildren, my brother's sons, my sister's sons and my cousins".

The strike, which Israel has yet to comment on, came as there were no signs of progress in mediation efforts led by the United States, Egypt and Qatar, seeking an end to the war.

The fighting was sparked by Hamas's October 7 attack on southern Israel that resulted in the deaths of 1,170 people, mostly civilians, Israeli figures show.

Israel's retaliatory offensive has killed at least 33,482 people in Gaza, mostly women and children, according to the health ministry in the Hamas-run territory.