JERUSALEM - Six workers for the U.N. agency for Palestinian refugees were among those killed when two Israeli airstrikes hit a school and its surroundings in a central Gaza refugee camp, the agency said Thursday, adding that it was the “highest death toll among our staff in a single incident.”

At least 18 people were killed and 18 injured in Wednesday’s attack, which struck the al-Jaouni school run by the U.N. Relief and Works Agency (UNRWA), Gaza Civil Defense spokesman Mahmoud Basal said in a statement. The school has been sheltering displaced Palestinians. The Israel Defense Forces said it was targeting Hamas militants.

In a statement, UNRWA said those killed in the two strikes in the Nuseirat refugee camp included the shelter’s manager. About 12,000 people are sheltering at the al-Jaouni school, which has been hit five times since the war began, the agency said. “No one is safe in Gaza,” UNRWA said in the statement. “No one is spared.”

Israel has repeatedly struck schools, hospitals and refugee camps over the past year of war in Gaza, causing mass civilian casualties.

“We need to see humanitarian sites protected, and that’s something that we continue to raise with Israel,” U.S. Secretary of State Antony Blinken said Thursday at a news conference in Warsaw. “At the same time, we continue to see Hamas hiding in, taking over and otherwise using these sites from which to conduct its operations and to pose an ongoing threat, and that, of course, has to stop, because those actions are endangering civilians.”

In a statement, the IDF said it conducted “a precise strike on terrorists who were operating inside a command and control center embedded within a compound that previously served” as a school. It listed the names of nine Hamas members it said were killed in the strike, including two it said worked simultaneously for UNRWA. The Israeli military said it has asked UNRWA for names and details of all workers the U.N. agency claimed were killed in the attack but that it has not received them.

In a statement shared by spokeswoman Juliette Touma, UNRWA said the IDF has not made any request for a list of workers killed in the strike and that the names released by the military in its statement “had not been flagged to us before by the Israeli authorities in previous occasions prior to today.”

Since the second week of the conflict, the al-Jaouni School has become a refuge for thousands of displaced Palestinians from Gaza City and other refugee camps across the Gaza Strip.

The school is now crowded with displaced families. Tents fill the yard, and clothes lines hang from the windows. Donkeys, horses and carts stand at the entrance.

Located on the main street of Nuseirat camp, it was initially designated as a safe zone when Israeli forces ordered evacuations to the southern Gaza Strip on Oct. 13. The camp is no longer in the current humanitarian safe zone.

At a briefing on Thursday, David Mencer, a spokesman for Israel’s National Public Diplomacy Directorate, said the IDF targeted a “command and control center” in Nuseirat that was “embedded inside a compound that previously served as the al-Jaouni school.

“When a school is no longer a school and becomes a Hamas command and control center, used to execute terrorist attacks against our troops and people, then it becomes a legitimate target,” he said. “A school being used for terror purposes is a school no more.”

Gaza resident Imad al-Hattab, 61, said in an interview that his brother, Naif al-Hattab, 59, an UNRWA employee and manager of the shelter, was one of the six killed in Wednesday’s strike.

“Naif studied Arabic literature at a university in Yemen and started his career as an Arabic-language teacher with UNRWA, eventually becoming a school principal. He went to the school every day, serving as supervisor of the shelter center,” Imad al-Hattab said.

He said his brother’s work as a teacher had benefited “thousands” of students in Gaza. Naif al-Hattab had three daughters and three sons, one of whom was killed in a previous Israeli strike on Gaza City.

“My brother Naif was a civilian who never carried a weapon. Yet, yesterday, he was targeted by an Israeli airstrike, despite his dedicated service. There is no justification for bombing a school and its displaced people and staff,” Imad al-Hattab said. “The loss of Naif has deeply affected us; his absence is irreplaceable due to his exemplary character and esteemed reputation among all.”

Dozens of Palestinians were killed Wednesday in other strikes across central and southern Gaza, and five were killed in a strike in Tubas in the West Bank, according to Palestinian officials and health workers.

Israel has repeatedly charged that hundreds of UNRWA workers are tied to militant groups in Gaza, but a report published by an independent review panel in April found that Israel had not provided evidence for this claim. Former French foreign minister

Catherine Colonna, who led the review group, said at the time that UNRWA needed to implement more robust vetting procedures but added that the U.N. agency is playing “a vital role in the humanitarian response in Gaza.”

The strikes on the UNRWA school drew fresh international condemnation, including from Egypt, Qatar and Jordan. British Foreign Secretary David Lammy described the reports of UNRWA workers being killed as “appalling.”

On Wednesday, UNRWA head Philippe Lazzarini condemned the “senseless killing, day after day” in Gaza in an X post, adding that at least 220 of the agency’s workers have been killed since Oct. 7. “The longer impunity prevails, the more international humanitarian law & the Geneva conventions will become irrelevant,” he wrote. According to the United Nations, more than 280 aid workers - most of them from UNRWA - have been killed in Gaza since Hamas’s Oct. 7 attack on Israel.

António Guterres, the U.N. secretary general, said in an X post on the killing of the six workers that “what’s happening in Gaza is totally unacceptable.” Tedros Adhanom Ghebreyesus, director general of the World Health Organization, called the deaths “terribly tragic” and renewed calls for a cease-fire.

- - - Here’s what else to know Hamas is ready to implement the cease-fire and hostage release proposal in the form announced by President Joe Biden in May, and without any new conditions, the group said Wednesday in a statement. Israeli Prime Minister Benjamin Netanyahu’s office said Thursday that Hamas “is trying to hide the fact that it continues to oppose a hostage release deal.” Complicating the deal are new requirements from Israel, including its insistence that its military will remain in the Philadelphi Corridor between Gaza and Egypt, as well as Hamas’s recent killing of six hostages.

Witness statements and video challenge the Israeli narrative on how Turkish American activist Aysenur Eygi was killed, a Washington Post investigation found. The IDF said Eygi was shot “unintentionally” during a “violent riot,” but The Post’s analysis shows clashes had subsided and protesters had retreated. Biden said in a Wednesday statement that he was “outraged and deeply saddened” by the death, adding that “the shooting that led to her death is totally unacceptable.”

Turkey’s Foreign Ministry that Eygi’s body will arrive in the country on Friday for her burial. “We will make every effort to ensure that this crime does not go unpunished,” the ministry wrote on social media Thursday.

The World Health Organization and its partners carried out the largest medical evacuation from Gaza since October - of 45 children and 52 adults who are sick or severely injured, along with 155 companions - on Wednesday, Tedros said on social media. More than 22,000 people - or around a quarter of those wounded in Gaza since the war began - have suffered “life-changing injuries,” the WHO separately said Thursday. The figures, which cover until July 23, come “in parallel with the ongoing decimation of the health system,” Richard Peeperkorn, the WHO’s representative in the occupied Palestinian territory, said in a news release.

The Islamist party that has tried to end Jordan’s peace agreement with Israel made significant gains in parliamentary elections, Jordanian media reported Wednesday. The Islamic Action Front, a Muslim Brotherhood affiliate, won 31 of 138 lower house seats, more than any other party, Jordan’s electoral commission announced. But the party will be curtailed by its minority position and the U.S. ally’s system of government, in which its king has significant power.

At least 41,118 people have been killed and 95,125 injured in Gaza since the war began, according to the Gaza Health Ministry, which does not distinguish between civilians and combatants but says the majority of the dead are women and children. Israel estimates that about 1,200 people were killed in Hamas’s Oct. 7 attack on Israel, including more than 300 soldiers, and says 342 soldiers have been killed since the launch of its military operation in Gaza.

Vinall reported from Seoul, Bisset from London and Taylor from Washington. Michael Birnbaum in Warsaw, Kareem Fahim in Beirut and Lior Soroka in Tel Aviv contributed to this report.

previous coverage

• Israeli airstrikes hit UN school and homes in Gaza, kill at least 34 people, hospitals say

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