Israel intensified its offensive in Gaza on Wednesday, leaving at least 16 Palestinians dead across the territory as the world awaited Hamas' response to U.S. President Donald Trump's proposed peace plan.

The dead included people who had sought refuge in a school sheltering the displaced in Gaza City. Al-Falah school in the city's eastern Zeitoun neighborhood was hit twice, minutes apart, according to officials at al-Ahli Hospital.

Among the casualties were first responders, they said. Five Palestinians were killed later Wednesday morning, when a strike hit people gathered around a drinking water tank on the western side of Gaza City, the same hospital said.

Also in Gaza City, the Shifa Hospital said it received the body of a man killed in a strike on his apartment west of the city.

Israeli strikes also hit the Nuseirat refugee camp in central Gaza, killing a husband and wife, the al-Awda hospital said. Another man was killed in a separate strike in the Bureij refugee camp, according to the same hospital.