Doctors and the Palestinian Red Crescent in Gaza say Israel has told them to evacuate a key hospital in Gaza City.
There are 400 patients being treated inside Al-Quds hospital and moving them is impossible, the Palestinian Red Cross says.
Around 14,000 civilians are also understood to be sheltering in the hospital and its grounds.
Overnight, thousands in Gaza broke into aid depots taking flour and other basic supplies, according to the UN relief agency for Palestinian refugees.
Phone lines and internet connections are slowly returning after more than a day of almost total communications blackout in Gaza.
The Israel Defense Forces (IDF) say more troops entered the territory overnight, while warplanes attacked more than 450 Hamas targets
Israel has been bombing Gaza since the 7 October Hamas attacks that killed 1,400 people and saw 230 people kidnapped as hostages
The Hamas-run health ministry in Gaza says more than 8,000 people have been killed since Israel’s retaliatory bombing began.