The Israeli army shelled Rafah in southern Gaza, destroying residential buildings and camps, leaving no safe place in the blockaded enclave.
The massive movement towards southern Gaza, accelerated by intense fighting and evacuation corridors, has seen tens of thousands of people flee in recent days.
But on Saturday, attacks hit buildings in Rafah, the area of the densely populated territory to which civilians were asked to evacuate.
An estimated 30,000 more Palestinians headed south through a corridor opened by the Israeli army on Friday, according to the UN humanitarian agency OCHA.
The Israeli military said about 150,000 Palestinians had moved south in recent days from areas in the northern strip where fighting is intense.
The main hospitals still operating do not have the medical resources necessary to cope with the number of casualties caused by continued bombing in the south.
More than 70 percent of Gaza’s 2.3 million residents have been displaced.