A day after Israel struck a convoy of ambulances transporting critically wounded patients from the al-Shifa Hospital to the Rafah border crossing, the Israeli army has intensified its bombardment of the Gaza Strip, hitting schools, mosques and more hospitals.

On Saturday morning an Israeli air missile struck the al-Fakhoora school run by the United Nations agency for Palestinian refugees (UNRWA) in the Jabalia refugee camp, killing at least 15 people and injuring 54, according to the Palestinian health ministry.

“The number [of deaths] is expected to rise,” said Muhammad Abu Silmeyeh, director of Al-Shifa Hospital.

Thousands of people displaced due to Israeli bombing in the Gaza Strip had taken refuge at the al-Fakhoora school.

A witness to the attack who lost family members in the bombing told Al Jazeera that four people in their family were killed or injured.

“We have nothing to do with anything related to the Hamas movement. The room only had children and women,” the witness added.

The attack on the school is the third major attack on the Jabalia camp.

It came hours after a deadly strike on the Osama bin Zaid School sheltering displaced families in the al-Saftawi area north of Gaza City, killing at least 20 people, according to local media.

On Saturday morning, the entrance of the al-Nasser Children’s Hospital in western Gaza City was also attacked, and several local media outlets reported civilian casualties.

The Health Ministry’s spokesperson has said an estimated 2,200 people, including 1,250 children, are currently buried under the rubble of destroyed buildings in Gaza.

At least 9,488 Palestinians have been killed in Israeli attacks on Gaza since October 7.