The death toll from an Israeli airstrike targeting a school sheltering displaced civilians in Gaza City’s Al-Daraj neighborhood has risen to 33, according to the Palestinian Civil Defense.

Spokesman Mahmoud Basal told Agence France-Presse that “the number of martyrs in the massacre at Fahmi Al-Jerjawi School in Al-Daraj has increased to at least 33, with dozens more injured — the majority of them children, including a number of women.”

The airstrike, which occurred in the early hours of Monday, is among the deadliest to hit civilian shelters in Gaza since the onset of the ongoing conflict. The Israeli military has not yet issued a statement regarding the incident.

Local rescue teams continue to search the rubble for survivors, as medical facilities across Gaza report mounting pressure from a surge in casualties.