Israel’s military on Monday said it has begun evacuating Palestinians from parts of Gaza’s southern city of Rafah, ahead of an expected military operation where roughly half of the enclave’s entire population is sheltering.

“For your safety, the IDF appeals to you evacuate immediately to the expanded humanitarian area in Al-Mawasi,” Avichay Adraee, the Israel Defense Force’s head of the Arab media division, wrote in a post on X, according to a Google translation from Arabic.

“The IDF will act with extreme force against terrorist organizations in your areas of residence, as it has done so far. Anyone who is close to terrorist organizations puts his life and the life of his family at risk,” the post said.

Al Mawasi is a small stretch of coastal scrub land, just over half a mile wide and 8.6 miles long, and is already host to several hundred thousand displaced Palestinians. More than 1.2 million people are currently sheltering in Rafah, most of whom fled other parts of the Gaza Strip, predominantly living in tents and without access to sufficient water, food, and basic medicine.

The White House — as well as the United Nations, WHO and other multinational organizations — has urged Israel against an offensive in Rafah, warning of catastrophic humanitarian consequences. Israeli President Benjamin Netanyahu said that an operation there is essential to his country winning the war against Hamas.