The Israeli military on Saturday issued evacuation orders for two buildings in Gaza City and urged Palestinian civilians to move to the south of the territory, as aid organizations warned that such an exodus could worsen the humanitarian crisis.

The military warned that it planned to strike two high-rise buildings in Gaza City and ordered people inside them and in nearby tents to leave. A short time later, it said it had attacked one of the towers.

A military spokesman said the buildings would be targeted because of Hamas activity inside or near them. Hamas has not commented on that accusation.

On Saturday, the military also said it was designating a humanitarian area in Al-Mawasi and Khan Younis, in the south of Gaza. The military said it would work to provide “field hospitals, water pipelines, and desalination facilities, along with the continued supply of food, tents, medicines, and medical equipment.”

In a statement, COGAT, the Israeli military agency that manages humanitarian affairs in Gaza, said the facilities were currently operational.

That statement could not be independently verified. Both Al-Mawasi and Khan Younis have been heavily damaged during the war, and it was not clear what humanitarian assistance was available.