More than 80 Palestinians were killed across Gaza on Thursday, according to health officials, as Israel intensified its strikes across the strip.

Sultan, was killed in an apartment in an Israeli strike west of Gaza City, a hospital statement said. The hospital is the Palestinian enclave’s largest medical facility north of Gaza City and has been a critical lifeline since the start of the war.

The attack raises more questions over whether Israel’s use of force is proportionate, as required by international law.