A spokesman said rescuers were struggling to recover a number of missing people believed to be trapped under the rubble at Mustafa Hafez school in the western Rimal neighbourhood.
The Israeli military said it had targeted a Hamas command and control centre inside the school, and that it had taken steps to mitigate risk of harming civilians.
Earlier, it announced that troops had recovered the bodies of six Israeli hostages being held in the Khan Younis area.
The men were among the two hundred and fifty one people kidnapped by Hamas-led gunmen in the 7 October attacks on southern Israel last year, when about one thousand, two hundred people were also killed.
Israel launching an air and ground campaign to destroy Hamas in response, during which more than forty thousand, one hundred and seventy people have been killed in Gaza, according to the territory’s Hamas-run health ministry.
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