Video from the scene showed body parts strewn across the ground and other bodies being carried away or covered with blankets, alongside empty food containers lying in pools of blood and charred mattresses, with a baby doll lying amid the rubble.

The Hamas-run media office said the air strikes occurred as people sheltering at the school were praying at dawn, causing many casualties.

"So far, more than 93 people have been killed, including 11 children and six women. There are unidentified remains," Palestinian Civil Defense spokesman Mahmoud Bassal said in a televised press conference.

He said there were about 6,000 people sheltering in the compound. Gaza health authorities have so far provided no details on casualties.

The Israeli military said the attack targeted about 20 Hamas and Islamic Jihad fighters operating at the site. In a statement, the Israeli military said the death toll had been exaggerated.

Israeli Lieutenant Colonel Nadav Shoshani said on social network X: "The complex and the mosque that were attacked were military bases of Hamas and Jihad operations."

"According to initial assessments, the numbers released by the Hamas-run Government Information Office in Gaza do not match the information held by the IDF (Israel Defense Forces)," Shoshani wrote.

Israel says Palestinian militant groups have infiltrated Gaza's civilian population, operating in schools, hospitals and designated humanitarian areas. Hamas and its allies deny this.

Hamas condemned the attack as a “heinous crime” and a serious escalation. Tens of thousands of displaced Palestinians have sought shelter in Gaza’s schools, most of which have been closed since the conflict began 10 months ago.

Palestinian President Palestinian Authority spokesman Nabil Abu Rudeineh called on Israel's ally the US to end its "blind support for the killing of thousands of innocent civilians, including children, women and the elderly".

Egypt's foreign ministry also condemned the airstrike, which came as mediators were pushing to resume ceasefire talks, saying the killing of Gaza civilians showed Israel had no intention of ending the conflict.

Egypt, the United States and Qatar have scheduled a new round of ceasefire talks for August 15 over concerns about a wider conflict involving Iran and its Lebanese ally Hezbollah.

Israeli Prime Minister Benjamin Netanyahu, who has said there will be no end to the conflict until Hamas no longer poses a threat to Israel, said he would send a delegation to the talks on August 15.

Hoai Phuong (according to Reuters)