The escalating conflict between Israeli forces and Palestinian armed groups has displaced hundreds of thousands of people, the UN reported on Monday.
Over 120,000 people have been internally displaced in Gaza due to concerns over their protection and the destruction of homes, said UN Spokesperson Stéphane Dujarric, speaking in New York.
The UN Relief and Works Agency for Palestine Refugees (UNRWA) is sheltering roughly 137,000 people in 83 of its schools across the Gaza Strip.
Six health care workers have been killed and four others injured, with seven health care facilities and nine ambulances damaged.
Mass displacement due to protection concerns and damage to civilian property has also been observed in Israel.
In Gaza, humanitarians report that damage to water, sanitation and hygiene facilitates has undermined services to more than 400,000 people. The Gaza Power Plant - now the only source of electricity - could run out of fuel within days.
Mr. Dujarric said the World Food Programme (WFP) has begun delivering fresh bread and canned food for up to 100,000 internally displaced Gazans sheltering in UNRWA schools.
WFP plans on starting to roll out assistance to up to 800,000 people, with food and cash assistance as the situation develops, provided the necessary funding is made available. The agency requires $16.8 million to reach 805,000 people in the next month.
Meanwhile, the UN peacekeeping force in Lebanon, UNIFIL, reported detecting explosions near Al-Boustan in the southwest on Monday afternoon.