KHAN YOUNIS, Gaza Strip (AP) — A flurry of Israeli airstrikes Tuesday on a refugee camp near Gaza City levelled apartment buildings, leaving craters where they once stood, as ground troops battled Hamas militants across northern Gaza and attacked underground compounds.

Buoyed by the first successful rescue of a captive held by Hamas, Prime Minister Benjamin Netanyahu rejected calls for a cease-fire and again vowed to crush Hamas’ ability to govern Gaza or threaten Israel following its bloody October 7 rampage, which ignited the war.

Several hundred thousand Palestinians remain in the northern part of Gaza, where Israeli troops and tanks reportedly have advanced on several sides of Gaza City, the sprawling urban centre.

In the Jabaliya refugee camp on Gaza City’s outskirts, at least six airstrikes destroyed a number of apartment blocks in a residential area, the Hamas-run Interior Ministry said. It reported a large number of casualties but did not immediately provide details.

Footage of the scene from Al-Jazeera TV showed at least four large craters where buildings once stood, amid a large swath of rubble surrounded by partially collapsed structures. Dozens of rescue workers and bystanders dug through the wreckage, searching for survivors beneath the pancaked buildings. A group of young men pulled two children from the upper floors of a damaged apartment block, cradling them as they climbed down.

More than half the territory’s 2.3 million Palestinians have fled their homes, with hundreds of thousands sheltering in packed UN-run schools-turned-shelters or in hospitals alongside thousands of wounded patients. Israeli strikes have hit closer to several northern hospitals in recent days, alarming medics.

Thousands of people broke into its aid warehouses over the weekend to take food, as supplies of basic goods have dwindled because of the Israeli siege.

There has been no central electricity in Gaza for weeks, and Israel has barred the entry of fuel needed to power emergency generators for hospitals and homes.

UNRWA, which hundreds of thousands of people in Gaza rely on for basic services even in normal times, says 64 of its staff have been killed since the start of the war, including a man killed alongside his wife and eight children in a strike late Monday.

“This is the highest number ever of UN aid workers killed in any conflict around the world in such a short time,” spokesperson Juliette Touma told The Associated Press. “UNRWA will never be the same without these colleagues.”

The war has also threatened to ignite fighting on other fronts. Israel and Lebanon’s Hezbollah militant group have traded fire daily along the border, and Israel and the US have struck targets in Syria linked to Iran, which supports Hamas, Hezbollah and other armed groups in the region.