Israel-Gaza updates: US ambassador to Israel demands return of hostages

As Sunday dawns in the Middle East, it will mark 100 days since the Israel-Hamas war began, the deadliest conflict between the two sides in recent history.

The fighting began on Oct. 7 when Hamas launched a surprise attack in southern Israel. Since then, Israel has launched numerous airstrikes and a ground offensive. The Israeli government has previously claimed it is defending itself.

More than 23,300 people have been killed in Gaza since the war began, according to the Hamas-run Gaza Health Ministry. Meanwhile, 1,200 people have been killed in Israel along with 520 Israel Defense Forces officers since Oct. 7.

Philippe Lazzarini, head of the U.N's Palestinian Relief Agency, issued a statement marking 100 days of the war, saying there are now 1.4 million people in U.N. shelters in Gaza and facing a “looming famine.”

Meanwhile, families of the Israeli hostages still held in Gaza are holding a series of events to mark 100 days since their captivity began.

-ABC News' Mary Kekatos and Patrick Reevell

About 577,000 people in Gaza, equal to a quarter of the population, are now starving, Arif Husain, chief economist for the U.N.'s World Food program, told ABC News.

Hussain has worked as an expert assessing hunger crises for 20 years and said, in terms of scale of severity and speed, he has never seen what is unfolding in Gaza right now, calling it “unprecedented.”

Even before the war with Israel, Gaza relied on humanitarian assistance to meet around 75% to 80% of its needs. With Israel now allowing very few supplies into Gaza, it has quickly run into massive shortages.

“If things continue as they are, or if things worsen, we are looking at a full fledged famine within the next six months," he said.

-ABC News' Patrick Reevell

A deal has been reached to get medicine to the hostages held by Hamas in Gaza over the next few days, according to the Israeli Prime Minister's office.

The families of the hostages are insisting that the Israeli war cabinet “demand visual proof that the medications did indeed reach the abductees, as a condition for any return from Israel.”

"After 98 days in the Hamas tunnels, all the abductees are in immediate danger and need life-saving medication,” the families said in a statement.

Israel on Friday called on the United Nations' top court to dismiss South Africa's request to halt its offensive in the Gaza Strip amid "grossly distorted" accusations of genocide.

During opening statements to a panel of judges at the International Court of Justice in The Hague, Israeli legal adviser Tal Becker said the country is fighting a "war it did not start and did not want."

"In these circumstances, there can hardly be a charge more false and more malevolent than the allegation against Israel of genocide," Becker added.

He noted that "Israel is in a war of defense against Hamas, not against the Palestinian people," and that the suffering of civilians during wartime does not amount to genocide.

"The key component of genocide, the intent to destroy a people in whole or in part, is totally lacking," he said.

-ABC News' Edward Szekeres and Morgan Winsor