At least three medics were injured in a drone strike on the Kamal Adwan Hospital in Beit Lahiya, northern Gaza.
The attack, the fifth on the facility in recent weeks, came amid ongoing Israeli military operations in the densely populated region.
Bombardments intensified overnight in central Gaza, where jets roared overhead.
Two people were killed in the bombing of residential buildings in Deir el-Balah.
Nearby, strikes expanded to the Bureij refugee camp, where a UN-run school was targeted.
One Palestinian was confirmed dead in the attack, which also burned down 15 makeshift tents sheltering hundreds of displaced families.
UN Secretary-General Antonio Guterres described the situation in Gaza as a humanitarian "nightmare."
“Aid is outrageously being blocked,” Guterres said on social media.
“It’s a crisis of political will and of respect for fundamental principles of international humanitarian law.”
The UN chief’s remarks followed the deaths of additional aid workers in Gaza and a two-month siege on northern areas by Israeli forces.
The siege has left residents without access to basic necessities, including water, food, and medicine.
Reports emerged from Rafah of civil defense workers recovering ten bodies from prior strikes.
The area, heavily militarized, posed significant risks to the rescuers, who lack essential equipment.
The death toll from Israeli genocide in Gaza has reached at least 44,502, with 105,454 wounded since October 7, 2023.