At least 22 people were killed in a strike on a school sheltering displaced people in southern Gaza City on Saturday, Reuters reported.
The Israeli military, however, stated that the attack targeted a Hamas command centre.
The Gaza health ministry reported that most of the victims were women and children.
The Hamas-run media office added that 13 children and six women were among the dead.
The military claimed the command centre was embedded in the compound, which was previously a school, accusing Hamas of using civilian facilities for military purposes. Hamas denied the allegation.
Reuters footage from the scene showed severe damage, with destroyed walls, burnt furniture, and holes in the ceiling, while survivors attempted to retrieve their belongings.
“The women and their children were sitting in the playground of the school, the kids were playing, and suddenly two rockets hit them,” said one witness, Said Al-Malahi, according to the Reuters report.
Some of the victims were carried away in blankets on donkey carts, while ambulances transported others.
Another witness, Ahmed Azzam, expressed frustration: “I couldn’t take it, I did not see a single man that is injured, it was all women and children, let the Arab countries rejoice, let them rejoice and clap for (Israeli Prime Minister Benjamin) Netanyahu and the United States of America.”
Meanwhile, in Rafah, four health workers were killed by an Israeli strike on ministry warehouses, according to the Gaza health ministry.
Ambulance crews were unable to reach the dead or tend to the wounded, the ministry added.
The Israeli military, in a statement, said its forces in Rafah had killed dozens of militants in recent weeks and dismantled military infrastructure and tunnel shafts.
A key obstacle in ceasefire negotiations has been Israel’s demand to maintain control over the southern Rafah-Egypt border. Hamas has said its focus is on ending the war and the withdrawal of Israeli forces from Gaza, while Israel insists the war will only conclude once Hamas is eradicated. Another challenge has been reaching an agreement on the exchange of Israeli hostages for Palestinian prisoners held by Israel.