Palestinian health officials called on Wednesday for a humanitarian corridor to three hospitals in northern Gaza that have come close to collapse as Israeli troops have cut off the area during almost two weeks of heavy fighting against Hamas.

Palestinian officials say hundreds were killed by a massive blast at a Gaza hospital on Tuesday, as humanitarian concerns mount over Israel’s deprivation of food, fuel and electricity to the enclave’s population.

The UN says 4,200 people have died on both sides in the fighting while large areas of Gaza have been "reduced to rubble."