"Palestine Red Crescent teams responded to 28 fatalities and 54 injuries following the Israeli occupation army's targeting of Rafida School," the organisation said, referring to a school in Deir el-Balah.

Gaza's Hamas-run health ministry issued the same death toll in a statement.

The Israeli army said in a statement the strike targeted Palestinian combatants operating from a command-and-control centre "embedded inside a compound that previously served as the (Rafida) School".

It did not give a toll but said the command-and-control centre was used "to plan and execute terrorist attacks against IDF (army) troops and the State of Israel".

Thursday's attack was the latest in a series of Israeli strikes on school buildings housing displaced Palestinians in Gaza, where fighting has raged for more than a year.

On September 26, at least 15 people were killed in another school-turned-shelter strike in northern Gaza's Jabalia camp, according to Gaza civil defence agency.

The Israeli military is currently engaged in an intense operation in Jabaliya.

The Israeli military accuses Hamas of hiding in school buildings where thousands of Gazans have sought shelter -- a charge denied by the Palestinian militant group.

At least 42,065 Palestinians, a majority of them civilians, have been killed in Israel's military campaign in Gaza since the war began, according to data provided by the health ministry in the Hamas-run territory.

The United Nations has acknowledged the figures to be reliable.

The October 7 attack that triggered the war resulted in the deaths of 1,206 people on the Israeli side, most of them civilians, according to an AFP tally based on official Israeli figures, which includes hostages killed in captivity.