Israeli military aircraft dropped thousands of leaflets on the northern Gaza Strip Friday warning residents in that part of the Palestinian territory to evacuate to its southern half. The Israeli military informed the United Nations late Thursday night that the entire population in northern Gaza should evacuate south almost immediately.

Stephane Dujarric, a U.N. spokesperson, told CBS News that liaison officers with the Israel Defense Forces informed the U.N. just before midnight Gaza time Thursday that the entire population north of Wadi Gaza should "relocate to southern Gaza within the next 24 hours."

According to the U.N., about 1.1. million people live in northern Gaza, the most densely populated part of the territory.

The U.N. "considers it impossible for such a movement to take place without devastating humanitarian consequences," Dujarric said, and it "strongly appeals for any such order, if confirmed, to be rescinded avoiding what could transform what is already a tragedy into a calamitous situation."

The U.N. response "to Israel's early warning to the residents of Gaza," Israel's U.N. Ambassador Gilad Erdan said, was "shameful" and ignores the brutality of the attack on Israel.

Early Friday local time, the IDF ordered Gaza City's hundreds of thousands of residents to move farther south in the Gaza Strip for their "own safety."

In response, Hamas called on Palestinians to stay put in their homes, according to The Associated Press.

"This is chaos, no one understands what to do," the AP quotes Inas Hamdan, an officer at the U.N. Palestinian refugee agency in Gaza City as saying.

The order comes as Israel continues to conduct relentless airstrikes on the Gaza Strip in the wake of Saturday's Hamas terror attacks, and prepares for an expected ground invasion of Gaza.

"Don't return to your homes until further notice from the Israel Defense Forces," the Israeli leaflets warned Palestinians who have few options for escape, adding that "all known and public shelters in Gaza City must be evacuated." 

The leaflets warned that anyone in Gaza who approached the security fence separating it from Israel risked being killed.  

According to the latest numbers from the U.N., at least 338,000 Gaza residents have been displaced since Hamas invaded southern Israel on Oct. 7, slaughtering civilians and prompting retaliatory airstrikes by Israel on Gaza.   

About 300,000 Israeli soldiers have amassed outside the border of the Gaza Strip. Israel Defense Forces international spokesperson Lt. Col. Jonathan Conricus on Wednesday did not explicitly say Israel was preparing a ground assault of Gaza, but noted the troops, along with tanks, armored vehicles and other artillery, were "making preparations for the next stage of the war which will come when the timing is opportune and fit for our purposes." 

Israeli officials said Thursday that at least 1,300 people have been killed in the Hamas invasion, and at least 2,800 more wounded.

At least 1,537 Gaza residents have been killed in Israel's counterattacks, including 500 children, and another 6,600 wounded, according to the Gaza Health Ministry.

Since the Hamas invasion, Israel has issued a complete blockade on Gaza, with no food, water, gas, medicine or electricity allowed in, putting the region on the brink of a humanitarian crisis. 

— Jordan Freiman contributed to this report.  

In:
• Hamas
• Israel
• United Nations
• Gaza Strip

Pamela Falk

Pamela Falk is the CBS News correspondent covering the United Nations, and an international lawyer.

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