An Israeli airstrike on a Gaza City school compound acting as a shelter for displaced Palestinian families killed around 100 people, the Gaza Civil Emergency Service has said.
Israel said the toll was inflated and that 19 militants were among the dead.
Video from the site showed body parts scattered around and more bodies being carried away and covered in blankets on the floor. Empty food tins lay in a puddle of blood, and burnt mattresses and a child's doll lay among the debris.
In another video, men prayed over a dozen body bags laid out on the ground of the Tabeen school complex.
The territory's Civil Emergency Service, which has a credible record in stating casualty numbers, and the Hamas-run government media office said in separate statements that the complex had been attacked as its occupants were performing dawn prayers.
"So far, there are more than 93 martyrs, including 11 children and six women. There are unidentified remains," Palestinian civil defence spokesperson Mahmoud Bassal told a televised press conference.
Appalled by the Israeli Military strike on al-Tabeen school and the tragic loss of life.
— David Lammy (@DavidLammy) August 10, 2024
Hamas must stop endangering civilians. Israel must comply with International Humanitarian Law.
We need an immediate ceasefire to protect civilians, free all hostages, and end restrictions…
Tens of thousands of displaced Palestinians have sought shelter in Gaza's schools, most of which have been closed since the war began 10 months ago.
Around 350 families had been sheltering at the compound, Bassal said - some of the hundreds of thousands of Palestinians displaced by Israel's onslaught on Gaza.
The upper floor housing families and the lower floor, used as a mosque, were both hit, he said.
Video from the scene showed walls blown out of a large building. Chunks of concrete and twisted metal lay on top of a blood-soaked floor, with clothing, toppled furniture and other debris.
A blackened car with the windows blown out was covered in rubble.
The Israeli military said the death toll was inflated.
"The compound, and the mosque that was struck within it, served as an active Hamas and Islamic Jihad military facility," Lieutenant Colonel Nadav Shoshani said on X.
He said the numbers published by the Hamas-run media office did not appear to correspond to the Israel Defense Forces' information, but the army provided no evidence of that.
An Israeli army official said the part of the mosque that was struck was reserved for men.
"This was verified by intelligence, and the strike was carried out using three small, precise munitions which cannot cause the scale of damage that the Palestinians are reporting," the official said.
Foreign Secretary David Lammy has said he is “appalled” by Israel’s air strike on a school in Gaza.
He tweeted: “Appalled by the Israeli Military strike on al-Tabeen school and the tragic loss of life.
“Hamas must stop endangering civilians. Israel must comply with International Humanitarian Law.
“We need an immediate ceasefire to protect civilians, free all hostages, and end restrictions on aid.”
The Israeli military acknowledged a strike, claiming it hit a Hamas command centre within the school.
If the death toll is correct, it would be one of the deadliest strikes in the 10-month-old war between Israel and Hamas.
The facility, like almost all of Gaza's schools, has been used as a shelter for people who have been forced to flee their homes by the war.
The strike hit without warning in the early morning before sunrise as people were praying at a mosque inside the school, witness Abu Anas told the Associated Press.
"There were people praying, there were people washing and there were people upstairs sleeping, including children, women and old people," he said.
"The missile fell on them without warning. The first missile, and the second. We recovered them as body parts."
Three missiles ripped through the school and the mosque inside, where about 6,000 displaced people were taking shelter from the war, said Mahmoud Bassal, a spokesperson for the Civil Defense first responders.
Many of the casualties were women and children, he said.
On Saturday, the Israeli military said the school was located next to a mosque serving as a shelter for Gaza City residents.
According to the United Nations, 477 out of 564 schools in Gaza have been directly hit or damaged in the war as of July 6.
In June, an Israeli strike on a school sheltering displaced Palestinians in central Gaza killed at least 33 people, including 12 women and children, according to local health officials.
Israel has blamed the civilian deaths in Gaza on Hamas, saying the group endangers noncombatants by using schools and residential neighbourhoods as bases for operations and attacks.
The strike came as American, Qatari and Egyptian mediators renewed their push for the two parties to achieve a cease-fire agreement that could help calm soaring tensions in the region following the assassination of top Hamas political leader Ismail Haniyeh in Tehran and a senior Hezbollah commander in Beirut.
Israel's campaign in Gaza has killed more than 39,600 Palestinians and wounded more than 91,700 others, according to the enclave's Health Ministry.
The war was triggered by Hamas' October 7 attack, in which militants from Gaza stormed into southern Israel, killing around 1,200 people and abducting 250 others.
More than 1.9 million of Gaza's pre-war population of 2.3 million have been driven from their homes.
