Gaza's civil defence agency said Israeli air strikes on Sunday killed at least 12 people, including young children, mostly in the south of the besieged Palestinian territory.

Civil defence spokesman Mahmud Bassal told AFP that Israeli fighter jets hit three tents overnight where dozens of displaced people were sheltering in the southern city of Khan Yunis.

"Eight people, including four children aged two to five and two women" were killed, Bassal said.

AFP footage showed rescuers working in the dark, evacuating a wounded baby from the site of the strike as well as two bodies, one of them in a white plastic bag and another wrapped in a blanket.

A separate strike on Khan Yunis later on Sunday killed three people, Bassal said.

One person was killed and three others wounded when a group of civilians came under attack in Gaza City, in the north, he added.

Bassal also said the Israeli military destroyed five houses with explosives in the east of Gaza City and fired artillery at the Abassa area east of Khan Yunis, without reporting any casualties.

The Israeli military did not comment on specific incidents but said its air force had struck "more than 50 terror targets across the Gaza Strip" since Saturday.

Israel resumed its offensive in Gaza on March 18 after a two-month truce in the war, triggered by Palestinian militant group Hamas' 7 October 2023 attack.

The Hamas attack resulted in the deaths of 1,218 people, mostly civilians, according to an AFP tally based on official figures.

The health ministry in Hamas-run Gaza said on Sunday that at least 2,720 people have been killed since Israel resumed its campaign, bringing the overall death toll since the war broke out to 52,829.