Israeli forces battled Palestinian militants Wednesday near the main hospital in Gaza’s second-largest city of Khan Younis, where medics said hundreds of patients and thousands of displaced people were unable to leave because of the fighting.

Israel has ordered residents to leave a swathe of downtown Khan Younis that includes Nasser and two smaller hospitals as it pushes ahead with its three-month-old offensive against Hamas.

The UN humanitarian office said the area was home to 88,000 Palestinians and was hosting another 425,000 displaced by fighting elsewhere.

The aid group Doctors Without Borders said its staff was trapped inside Nasser Hospital with some 850 patients and thousands of displaced people because the surrounding roads were inaccessible or too dangerous. Nasser Hospital is one of only two hospitals in southern Gaza that can still treat critically ill patients, the group said. Gaza’s health ministry also said the hospital had been isolated.

The Israeli military said its forces were battling militants inside Khan Younis after completing their encirclement of the city the day before. It said aircraft were striking targets as part of the operations there and had also targeted suspected militants in central and northern Gaza.

Thousands of people fled south from Khan Younis on Tuesday toward the town of Rafah. The UN says some 1.5 million people — around two-thirds of Gaza’s population — are crowded into shelters and tent camps in and around Rafah, which is on the border with Egypt.

Even there, Palestinians have found little safety, with Israel regularly carrying out strikes in and around the town. Palestinian witnesses said that in recent days Israeli soldiers and tanks had pushed into parts of Muwasi, a sandy area along the coast that Israel had declared a safe zone, where tens of thousands of people were living in tents without basic services.

In all, some 1.7 million people have been displaced within Gaza, according to the UN refugee agency. Most have fled from the north, where Israel’s air and ground offensive has reduced entire neighbourhoods to shelled-out wastelands, raising the question of whether residents will ever be able to return.

Gaza’s health ministry says the offensive has killed at least 25,490 people — the majority women and children — and wounded another 63,354. Its count does not differentiate between civilians and combatants. UN officials have expressed fears that even more people could die from the disease, with at least one-quarter of the population facing starvation.

Israeli Prime Minister Benjamin Netanyahu has vowed to press ahead with the offensive until “complete victory” against Hamas, which started the war with its assault across the border on October 7, killing some 1,200 people and abducting another 250.

Israeli divisions

Netanyahu says Israel is also committed to returning the over 100 hostages that remain in captivity after most of the others were freed in exchange for the release of Palestinian prisoners during a November ceasefire.

But many Israelis, including at least one member of Netanyahu’s war cabinet, say that’s impossible without reaching another agreement with Hamas. The militant group says it won’t release any more hostages until Israel ends its offensive.