"Tonight we conducted a targeted operation into Al-Shifa hospital," said Major General Yaron Finkelman, the head of Israeli military operations in Gaza. "We continue to move forward."

The Palestinian health ministry in Gaza said Thursday that Israeli bulldozers had "destroyed parts of the southern entrance" of the hospital.

Both Israel and its top ally the United States claim that Hamas has a command centre below the Al-Shifa complex, which has become a focal point in the war.

The Palestinian group and directors at the hospital have denied the charge.

Before Israel first sent troops into the hospital complex on Wednesday, UN agencies estimated that 2,300 patients, staff and displaced civilians were sheltering at Shifa.

Israel's army claimed an initial raid had uncovered military equipment, weapons and what spokesman Daniel Hagari described as "an operational headquarters with comms equipment".

Witnesses have described conditions inside the hospital as horrific, with medical procedures performed without anaesthetic, families with scant food or water living in corridors, and the stench of decomposing corpses filling the air.

"The protection of newborns, patients, medical staff and all civilians must override all other concerns," UN humanitarian chief Martin Griffiths said. "Hospitals are not battlegrounds."

A journalist in contact with AFP, trapped inside Al-Shifa, said that Israeli soldiers, some wearing face masks, shot in the air and ordered young men to surrender when they first entered the facility.

About 1,000 male Palestinians, hands above their heads, were in the courtyard, some of them stripped naked by Israeli soldiers checking them for weapons or explosives, the journalist said.

US President Joe Biden said Hamas had committed a war crime by housing "their headquarters, their military hidden under a hospital".

But he warned Israel to be "incredibly careful" of harming civilians during the operation.

 'Urgent' pauses 

The UN Security Council on Wednesday set aside deep divisions over the conflict to agree on a resolution calling for "urgent and extended humanitarian pauses" in fighting.

The resolution -- which passed thanks to abstentions from the United States, Britain and Russia -- called on Hamas and Israel to protect civilians, "especially children".

Israel has agreed to temporary localised pauses in fighting but has rejected calls for a broader ceasefire.

"The UN Security Council's resolution is disconnected from reality and is meaningless," Israel's Ambassador to the United Nations, Gilad Erdan, wrote on X.

He also reiterated the Israeli government's war aims, saying: "Israel will continue to act until Hamas is destroyed and the captives are returned."

The Israeli foreign ministry called Thursday on the Security Council and the international community to "stand firm on the prompt release" of all the kidnapped.

"Extended humanitarian pauses are untenable as long as 239 abductees remain in the hands of Hamas terrorists," it said.

Home front 

Polls in Israel show widespread public support for military action against Hamas following the October 7 operation.

Prime Minister Benjamin Netanyahu on Wednesday boasted there was no safe place for the Hamas fighters and "no place in Gaza" the army would not reach.

"They told us we wouldn't reach the outskirts of Gaza City and we did, they told us we wouldn't enter Al-Shifa and we did," he said.

But Netanyahu, who has led Israel on and off for 16 years, is under intense domestic pressure to account for political and security failings surrounding the Hamas's operation.

Protesters have taken to the streets demanding more be done to release the captives.

Once the war in Gaza has concluded, a political reckoning is expected.

Israeli opposition leader Yair Lapid on Wednesday called for that reckoning to come even sooner, demanding that Netanyahu step down.

"Netanyahu should leave immediately," he told Israel's N12 channel. "We need change, Netanyahu cannot remain prime minister."

"We cannot allow ourselves to carry out a long campaign under a Prime Minister who has lost the people's trust."

Speaking to reporters on Wednesday, Biden said he was "mildly hopeful" there would be a deal to free the captives.

"I don't want to get ahead of myself here because I don't know what's happened in the last four hours, but we have gotten great cooperation from the Qataris," he said when asked about progress on freeing the captives.

Qatar, which hosts a Hamas political office and also has behind-the-scenes diplomatic links with Israel, has led negotiations for the release of the captives.