Several Western diplomats, the mediators of ceasefire-for-hostage talks and numerous Muslim countries denounced Israel over a deadly airstrike on a school in Gaza, where the military said at least 20 Hamas and Palestinian Islamic Jihad terrorists were operating.

“Horrified by images from a sheltering school in Gaza hit by an Israeli strike, with reportedly dozens of Palestinian victims. At least 10 schools were targeted in the last weeks. There’s no justification for these massacres,” EU foreign policy chief Josep Borrell wrote on X.

The Gaza Strip’s Hamas-run civil defense agency said over 90 people were killed in Saturday’s airstrike on the school, describing the incident as a “horrific massacre.”

The IDF said it targeted a Hamas command room inside the building and expressed heavy skepticism about the figures from the Gaza-ruling terror organization, saying the numbers appeared to have been inflated.

It was unclear how many were actually killed and how many of the casualties were combatants.

UK Foreign Minister David Lammy said that Britain was “appalled” at Israel’s deadly airstrike and called for “an immediate ceasefire.”

“Appalled by the Israeli Military strike on al-Tabeen school and the tragic loss of life,” Lammy wrote on X, adding: “We need an immediate ceasefire to protect civilians, free all hostages, and end restrictions on aid.”

France said it condemned the strike “in the firmest of terms.”

“For several weeks, school buildings have been repeatedly targeted, with an intolerable number of civilian victims,” it said.

In recent months, dozens of airstrikes have been carried out against Hamas sites embedded within schools and other sites used as shelters for civilians, according to the IDF.

The IDF said two days ago that it had struck Hamas command and control centers in schools in the Daraj and Tuffah neighborhoods. And on Monday, it said the commander of Hamas’s Sheikh Radwan Battalion was killed in an airstrike at another school in Gaza City.

According to military assessments, Hamas operatives are struggling to remain inside tunnels as the long war drags on and are therefore increasingly moving to above-ground sites, while hiding among innocents.

Egypt claimed Israel’s “deliberate killing” Saturday of Palestinians showed that it lacks a political will to end the war in Gaza amid negotiations for a deal that would see hostages released by Hamas in return for a ceasefire.

Qatar, which like Egypt has been mediating in the talks between Israel and Hamas, demanded an urgent probe after the strike.

The Qatari foreign ministry said it renewed the Gulf emirate’s “demand for an urgent international investigation, including the dispatch of independent UN investigators, to ascertain the facts regarding the Israeli occupation forces’ continued targeting of schools and shelters for displaced persons.”

The foreign ministry of Lebanon — from where Hezbollah has been launching near-daily attacks on Israel in solidarity with Gaza since the Hamas-led October 7 atrocities that started the ongoing fighting — said the strike showed Israel’s intention to “extend the war,” while Saudi Arabia urged the end to the “mass slaughter in Gaza.”

Iran’s foreign ministry spokesperson claimed the strike was proof of “genocide, war crimes and crimes against humanity simultaneously” and called for broad action by Muslim countries against Israel, and support for Palestinian “resistance.”

Turkey, another supporter of Hamas like Iran, denounced a “new crime against humanity” after Israel’s attack, according to a foreign ministry statement.

“Israel has committed a new crime against humanity by massacring more than 100 civilians who had taken refuge in a school,” the ministry said, accusing Prime Minister Benjamin Netanyahu of wanting “to sabotage ceasefire negotiations.”

Francesca Albanese, the United Nations special rapporteur on the rights situation in Palestinian territories, accused Israel of committing “genocide” in its war against Hamas after the strike.

“Israel is genociding [sic] the Palestinians one neighborhood at the time, one hospital at the time, one school at the time, one refugee camp at the time, one safe zone at the time,” she said on social media platform X.

The Times of Israel exposed Albanese’s history of antisemitism, including comments on how the “Jewish lobby” was in control of the US, in an investigation in 2022.

Albanese, who is tasked with investigating Israeli activities in the Palestinian territories, has not faced any repercussions from the UN or issued a clear apology for her past statements. She has continued to lob accusations of war crimes against Israel in recent months.

The war in Gaza has been ongoing since October 7 when Hamas launched an unprecedented attack on Israel in which terrorists murdered some 1,200 people, mostly civilians, and took 251 hostages. One hundred and eleven of the hostages are still held; the IDF has established that 39 of them are dead.

In response, Israel launched a ground invasion of Gaza with the proclaimed objectives of dismantling Hamas and getting the hostages back.

The Hamas-run Gaza health ministry says more than 39,000 people in the Strip have been killed or are presumed dead in the fighting so far, though the toll cannot be verified and does not differentiate between civilians and fighters. Israel says it has killed some 15,000 combatants in battle and some 1,000 terrorists inside Israel during the October 7 attack. Israel has said it seeks to minimize civilian fatalities and stresses that Hamas uses Gaza’s civilians as human shields, fighting from civilian areas including schools and mosques.

Israel’s toll in the ground offensive against Hamas in Gaza and in military operations along the border with the Strip stands at 331.