Israel kept up its barrage of the Gaza Strip on Thursday despite intensifying international calls to reduce civilian casualties and address a mounting humanitarian catastrophe.

In central Rafah, in the south of the coastal enclave, 24 people were killed in an Israeli strike that hit two houses, Hamas media said early on Thursday. There was no immediate confirmation from the Palestinian health ministry.

White House national security adviser Jake Sullivan, who is visiting the region and will be in Israel on Thursday and Friday, would discuss with the Israelis the need to be more precise with their strikes against Hamas targets, spokesperson John Kirby told reporters.

Sullivan met with officials of Saudi Arabia on Wednesday and discussed "broader diplomatic efforts to maintain stability across the region and prevent the Israel-Hamas conflict from expanding," another U.S. official said.

Nearly half of the air-to-ground munitions that Israel has used in Gaza in its war with Hamas since Oct. 7 have been unguided, otherwise known as "dumb bombs," according to a new U.S. intelligence assessment reported by CNN.

The news outlet said the assessment was compiled by the Office of the Director of National Intelligence and described to CNN by three sources who have seen it.

About 40-45% of the 29,000 air-to-ground munitions Israel has used have been unguided and the rest have been precision-guided munitions, the CNN report added.

Israel says its bombardment and ground offensive in Gaza is aimed at annihilating Hamas, the group whose fighters stormed across the border fence from Gaza on Oct. 7, killing 1,200 Israelis, mostly civilians, and seizing 240 hostages.

Since then, Israel has laid much of the Palestinian enclave to waste. At least 18,608 people have been killed and 50,594 injured in Israeli strikes on Gaza, according to Gaza's health ministry.

The coastal strip is now facing a public health disaster due to the collapse of its health system and the spread of disease, the U.N. humanitarian office said.

"We've got a textbook formula for epidemics and a public health disaster," said Lynn Hastings, the U.N. Humanitarian Coordinator for the Occupied Palestinian Territory.

TANKER ATTACKED

Fears of the conflict spreading in a volatile region remain.

A tanker in the Red Sea off Yemen's coast was fired on by gunmen in a speedboat and targeted with missiles, maritime sources said on Wednesday. It is the latest incident to threaten the vital shipping lane after Yemeni Houthi forces, which are backed by Iran, warned ships not to travel to Israel.

The cost of the Israel-Hamas war to neighbours Lebanon, Egypt and Jordan in terms of loss of GDP may amount to $10.3 billion or 2.3%, and might double if the conflict lasts six more months, a study commissioned by the U.N. Development Programme said.

The Biden administration is delaying the sale to Israel of more than 20,000 U.S.-made rifles over concerns about increasing attacks by Israeli settlers on Palestinians in the West Bank, two sources familiar with the matter said.

Some 271 Palestinians have been killed by Israeli security forces, including 69 children, in the occupied West Bank this year, the U.N. Palestinian refugee agency said.

At least 288 displaced people in shelters run by the agency have been killed in Gaza since Oct. 7, the agency added in a post on X.

The number of Israeli soldiers killed in the ground offensive has reached 115, and more than 600 wounded, according to an Israeli military website.

"Your heroism, and of those who unfortunately fell and we couldn’t bring them to this state of rehabilitation, are the light which repels the darkness, and in this room there is so much light," Lieutenant General Herzi Halevi, chief of Israel's General Staff, told injured soldiers during a ceremony for the Jewish festival of Hanukkah in Ramat Gan.

PROTESTS, VIGILS

Some Biden administration staffers held a vigil in front of the White House late on Wednesday to call on Washington to support a ceasefire in Gaza.

The group of around 60 people carried a banner that read: "President Biden, your staff demands a ceasefire."

"We were horrified by the brutal October 7 attacks on Israeli civilians, and have been horrified by the disproportionate response by the Israeli government, which has indiscriminately killed thousands of innocent Palestinian civilians in Gaza and displaced over a million more," the protesters said in a statement read by Josh Paul, a former State Department official who resigned a few weeks ago.

In New York, a demonstration was held demanding the release of the remaining 135 hostages held in Gaza.

Most Israelis say the army should not back off its unrelenting offensive to crush Hamas.

"It's awful. It's awful that there are so many civilian casualties," said Jerusalem resident Adam Saville. "But this is war, and that's what happens in war."

Israel-Gaza live updates: Israeli commander among 10 killed overnight, IDF says

Latest Developments

Dec 13, 11:39 AM

No more children's vaccines available in Gaza: Gaza Ministry of Health

Children's vaccines have run out completely in Gaza, according to the Gaza Ministry of Health.

This "will cause catastrophic health repercussions on children's health and the spread of diseases, especially among the displaced in overcrowded shelter centers," Gaza Health Ministry spokesman Dr. Ashraf Al-Qudra warned.

Dec 13, 11:23 AM

Biden meets with families of American hostages

President Joe Biden met privately Wednesday with families of Americans taken hostage by Hamas, according to the White House.

Participants included: Yael Alexander, Adi Alexander, Ruby Chen, Roy Chen, Ronen Neutra, Orna Neutra, Jonathan Dekel-Chen, Gillian Kaye, Aviva Siegel, Elan Siegel, Shir Siegel, Hanna Siegel and Liz Naftali.

Secretary of State Antony Blinken and Jon Finer, White House deputy national security adviser, also participated in the meeting.

Jon Polin and Rachel Goldberg, whose 23-year-old son, Hersh, was taken hostage, and Iris Haggai, whose parents were believe to be kidnapped, joined the meeting by phone.

-ABC News’ Molly Nagle

Dec 13, 11:13 AM

US issues 4th round of sanctions against Hamas officials

The U.S. has announced another round of sanctions against Hamas officials, including key operatives in Turkey who allegedly worked to transfer money into Gaza to fuel Hamas operations.

These sanctions, imposed in coordination with the United Kingdom, are the fourth round imposed by the U.S. since Hamas’ Oct. 7 attacks on Israel.

The sanctions reflect the administration’s "commitment to dismantling networks that support Hamas funding streams as part of our continuous effort to prevent and deter its terrorist activity," State Department spokesperson Matt Miller said in a statement.

-ABC News’ Shannon Crawford

Dec 13, 10:13 AM

Nearly 200 aid trucks entered Gaza on Tuesday

There were 197 humanitarian aid trucks that crossed through the Gaza-Egypt Rafah border crossing on Tuesday, entering Gaza, according to COGAT, the Israeli agency for civilian coordination with the Palestinians.

Eighty of those trucks were inspected at the Kerem Shalom crossing at the Israel-Gaza-Egypt border, which opened for the first time on Tuesday to expand the amount of aid entering Gaza.

Dec 13, 8:38 AM

US urges Israel to be as 'deliberate as possible' in Gaza strikes

U.S. officials are continuing to urge the Israeli military to be "as careful and deliberate as possible" as it strikes targets within Gaza, National Security Council spokesperson John Kirby said.

"We want to make sure they get as precise targets as possible to limit civilian casualties," Kirby told ABC News' George Stephanopoulos on "Good Morning America" on Wednesday.

He added that the U.S. will continue to support Israel, including making sure "they have the weapons to go after Hamas wherever they are inside Gaza."

-ABC News' Kevin Shalvey

Dec 13, 6:27 AM

IDF commander among 10 killed overnight, IDF says

The Israel Defense Forces reported the deaths of 10 service members overnight, including a high-ranking officer, making Tuesday one of the deadliest days for the country's military since the ground invasion began in Gaza.

Nine troops died in a single incident, an ambush in northern Gaza, officials said, marking the deadliest incident over the past month for the IDF.

At least 115 service members have been killed since Israel’s ground invasion began. A total of 444 have been killed since Oct. 7, officials said.

-ABC News’ Jordana Miller and Joe Simonetti

Dec 12, 7:31 PM

Biden says he doesn't know if there are hostages in Gaza tunnels

President Joe Biden said he does not know for a fact if there are any hostages in the tunnels under Gaza amid reports that Israel began flooding some of them to target Hamas.

"There [are] assertions being made that they're quite sure there are no hostages in any of these tunnels, but I don't know that for a fact," Biden told reporters during a briefing on Tuesday. "I do know that, though, that every civilian death is a national tragedy."

Asked if he has spoken to Israeli Prime Minister Benjamin Netanyahu about how long he believes the operation in Gaza should last, Biden declined to give a timeline.

"I want to make sure that we don't forget what we're doing here. We have to support Israel because they're an independent nation," he said, adding that the "brutality" of Hamas' Oct. 7 attack on Israel is "beyond comparison."

-ABC News' Molly Nagle

Dec 12, 4:43 PM

UN resolution demanding immediate cease-fire passes by large majority

A United Nations resolution demanding an "immediate humanitarian cease-fire" in Gaza passed by a large majority during an emergency session of the U.N. General Assembly.

The resolution is not legally binding but carries symbolic weight.

Ten countries -- including the U.S. and Israel -- voted against the resolution, while 153 member countries voted in favor of the resolution.

Before the vote, U.S. Ambassador to the U.N. Linda Thomas-Greenfield said the proposed resolution again failed to condemn Hamas. Thomas-Greenfield said the U.S. is working toward “sustainable peace” and that the country agrees with some aspects of the resolution.

-ABC News’ Ellie Kaufman

Dec 12, 4:35 PM

Israel pumping seawater into some Gaza tunnels

Israel has recently started to pump seawater into Hamas’ underground network of tunnels, two U.S. officials confirmed to ABC News. It seems the flooding has been limited as Israel evaluates the effectiveness of this strategy compared to its other techniques.

The development was first reported by The Wall Street Journal. The Israeli Defense Forces has not publicly commented.

ABC News previously reported that Israel was exploring a range of options to take out Hamas’ tunnels, including flooding them with seawater -- an approach some worried could have devastating long-term environmental impacts and other ramifications for Gaza’s civilian population.

In 2015, Egypt used seawater to flood a section of tunnels in the southern stretch of the enclave to disrupt smuggling activity, which led to complaints about damaged homes and crops, as well as contaminated water supplies.

-ABC News’ Luis Martinez, Shannon Crawford and Justin Gomez

Dec 12, 3:44 PM

Biden says Netanyahu needs to 'strengthen' and 'change' the Israeli government

President Joe Biden said at a campaign reception that Israel is starting to lose support and Israeli Prime Minister Benjamin Netanyahu needs to "strengthen" and "change" the government to find a long-term solution to the Israeli-Palestinian conflict.

"This is the most conservative government in Israel's history," Biden said, adding that the government "doesn't want a two-state solution."

"You cannot say there's no Palestinian state at all in the future. And that's going to be the hard part," he said.

"Bibi's got a tough decision to make," Biden said, referring to Netanyahu.

Biden added, "In the meantime, we're not going to do a damn thing other than protect Israel in the process."

The president also recounted a recent conversation with Netanyahu, saying, "It was pointed out to me -- I’m being very blunt with you all -- it was pointed out to me that -- by Bibi -- that. 'Well, you carpet-bombed Germany. You dropped the atom bomb. A lot of civilians died.'"

"I said, 'Yeah, that’s why all these institutions were set up after World War II to see to it that it didn’t happen again -- it didn’t happen again," Biden said. "Don’t make the same mistakes we made at 9/11. There was no reason why we had to be in a war in Afghanistan at 9/11. There was no reason why we had to do some of the things we did."