Israeli forces pushed Sunday into southern Gaza, where hundreds of thousands of civilians have fled in search of shelter from bombardments and intense fighting with Hamas militants.

Aid groups have sounded the alarm on the "apocalyptic" humanitarian situation in the Palestinian territory, warning it is on the brink of being overwhelmed by disease and starvation.

Hamas, which runs Gaza, said Sunday that Israel had launched a series of "very violent raids" targeting the southern city of Khan Yunis and the road from there to Rafah, near the border with Egypt.

An Israeli occupation soldier shares a video on TikTok that shows him enjoying the vandalizing of civilian cars and the entrance to a girl school in Beit Lahiya, northern Gaza.

In his video caption, he said, "I stopped counting how many neighborhoods I erased." pic.twitter.com/0cgdXkh34k
— Quds News Network (@QudsNen) December 10, 2023

A source close to Hamas and Palestinian militants Islamic Jihad told AFP both groups were involved in "fierce clashes" with Israeli forces on Sunday near Khan Yunis. An AFP journalist reported strikes in the area.

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At least 17,700 people, mostly women and children, have died in two months of fighting in the narrow strip of territory, according to the latest figures from Gaza's Hamas-run health ministry.

Israel has vowed to eradicate Hamas after the group's unprecedented attacks on October 7, when its fighters broke through Gaza's militarised border, killed about 1,200 people, and seized hostages, according to Israeli officials.

Israel on Saturday said 137 captives remained in the Palestinian territory.

‼️Breaking | The Ministry of Health in Gaza: Sniper fire from the occupation army targets Dr. Ashraf Abu Mahady, the Director General of Pharmacy at the Ministry of Health, as he attempts to reach the drug warehouses. His job is to secure essential medical supplies for Al-Shifa… pic.twitter.com/UFpw3S8M9a
— Quds News Network (@QudsNen) December 9, 2023

With few options for safety, people across the Gaza Strip sought refuge in hospitals on Saturday.

In the northern Gaza City, an AFP journalist said thousands were sheltering in the Al-Shifa hospital, which is no longer functioning and partly destroyed following an Israeli raid last month.

Hundreds of makeshift tents fashioned from scraps of fabric and plastic filled the hospital's courtyards and garden amid collapsed walls.

Suheil Abu Dalfa, 56, from the city's Shejaiya district, said he had fled heavy bombardment by Israeli planes and tanks.

"It was madness. A shell hit the house and wounded my 20-year-old son," he told AFP.

"We fled to the Old City, everything was just strikes and destruction... we didn't know where to go," he said.

"We don't know if they will storm the hospital again."

In central Gaza, Hamas health authorities said Saturday that 71 dead bodies had arrived at the Al-Aqsa Martyrs Hospital in Deir al-Balah over 24 hours.

And in the south of the territory, 62 dead bodies had arrived at Nasser hospital in Khan Yunis, the health authorities said.

An AFP correspondent at the hospital saw a child on a makeshift stretcher and others waiting for care on the floor, while firefighters outside tried to douse a burning building hit by an Israeli strike.

The situation "is not just a catastrophe, it's apocalyptic", said Bushra Khalidi of Oxfam.

- 'Death sentence for children' -

An estimated 1.9 million of Gaza's 2.4 million people have been displaced.

Blocked from leaving the narrow territory, they have turned Rafah, near the crossing with Egypt, into a vast camp.

The United Nations children's agency said Saturday that nearly one million children had been forcibly displaced by the conflict.

With fighting intensifying in southern Gaza, where Israel previously urged civilians to seek shelter, children are running out of safe places to go.

"They are now being pushed further and further south into tiny, overcrowded areas without water, food, or protection, putting them at increased risk of respiratory infections and waterborne disease," said Adele Khodr of UNICEF.

"The restrictions and challenges being placed on the delivery of lifesaving aid going into and across the Gaza Strip are another death sentence for children."

As alarm grew over Gaza's worsening humanitarian situation, Israeli army chief Herzi Halevi urged his forces to "press harder" in their campaign.

"We're seeing more and more terrorists killed, more and more terrorists wounded, and in recent days we're seeing terrorists surrendering -- this is a sign their network's falling apart," he said at a ceremony in Jerusalem.

National Security Advisor Tzachi Hanegbi told Israeli TV that 7,000 "terrorists" had been killed, without elaborating on the source of the figure.

In Tel Aviv, some Israelis held a pro-peace demonstration.

Hundreds of others gathered in what has come to be known as Hostages Square, calling for action to save the captives held by Hamas with signs bearing messages such as "They trust us to get them out of hell".

The Israeli army says it has lost 93 soldiers in the campaign, with two others injured in a failed bid to rescue hostages on Thursday night.

Hamas said a hostage, 25-year-old Sahar Baruch, was killed in the operation, later confirmed by his kibbutz community in Beeri, one of the worst hit on October 7.

- UN force hit -

A rare UN Security Council vote on a ceasefire in the conflict was vetoed on Friday by the United States, whose envoy Robert Wood said the proposal was "divorced from reality" and would leave Hamas in power in Gaza.

Iran, which backs Hamas, warned of an "uncontrollable explosion in the situation of the region" following the veto.

In Yemen, Iran-backed Huthi rebels threatened on Saturday to attack any vessels heading to Israeli ports unless food and medicine were allowed into Gaza.

The French military said Sunday that one of its frigates had shot down two drones in the Red Sea that were heading towards the vessel from the coast of Yemen.

Regular exchanges between Israel and Lebanon's Iran-backed Hezbollah movement have further fuelled fears of a wider regional conflict.

Israel's army said it retaliated on Saturday after unspecified "launches" from Lebanon, including with fighter jets.

A United Nations peacekeeping position in southern Lebanon was hit on Saturday without causing casualties, the UN force said, adding it was seeking to verify the source of the fire.

Violence has also surged in the Israeli-occupied West Bank, where the health ministry said three people were killed on Saturday.

The military earlier said it has arrested 2,200 people in the West Bank, 1,800 of them Hamas members, since the Israel-Hamas war began.