RAFAH, Gaza Strip (AP) — Israel launched heavy strikes across central and southern Gaza overnight and into Wednesday after broadening its offensive against Hamas to more areas where the military had told Palestinians to seek shelter earlier in the war.

Residents reported heavy bombing in the built-up Bureij refugee camp in central Gaza, in the southern city of Khan Younis and in the southern town of Rafah, areas where tens of thousands have sought refuge as much of northern Gaza was pounded to rubble.

“It was a night of hell. We haven’t seen such bombing since the start of the war,” said Rami Abu Mosab, speaking from the Bureij camp, where he has been sheltering since fleeing his home in northern Gaza.

He said warplanes flew overhead and gunfire and explosions echoed from the eastern edge of the camp — which, like others in Gaza, houses refugees from the 1948 war surrounding Israel’s creation and their descendants and now resembles other densely populated neighbourhoods.

A home near Abu Mosab’s shelter was hit, but no one was able to reach the area, he said. Mobile phone and internet service was down for several hours before being gradually restored on Wednesday, the latest of several such outages that have complicated rescue efforts.

With much of northern Gaza levelled, Palestinians fear a similar fate awaits other areas, including Khan Younis, where Israeli forces launched ground operations in early December, and a cluster of built-up refugee camps in central Gaza where the focus has shifted this week.

The military’s latest evacuation orders cover an area of central Gaza that was home to nearly 90,000 people before the war and now shelters more than 61,000 displaced people, mostly from the north, according to the UN humanitarian office.

Israel has said the bombing campaign and ground offensive are necessary to dismantle Hamas and prevent a repeat of its October 7 attack, in which militants broke through Israel’s formidable defences and killed some 1,200 people — mostly civilians — and abducted around 240. An estimated 129 remain in captivity after dozens were freed.

Achieving its goals, Israel has said, will take “many months.”

Its offensive is already one of the most devastating military campaigns in recent history. More than 21,100 Palestinians, most of them women and children, have been killed, including nearly 200 people in the last 24 hours, according to the Health Ministry in Hamas-ruled Gaza. The count doesn’t differentiate between civilians and combatants.

Some 85 per cent of Gaza’s population of 2.3 million Palestinians have fled their homes, crowding into smaller and smaller areas in recent weeks as the ground offensive has expanded. For many Palestinians, the exodus has echoes of the mass displacement in 1948 that they refer to as the Nakba, or catastrophe.

UN officials said a quarter of the territory’s population is starving under Israel’s siege, which allows in a trickle of food, water, fuel, medicine and other supplies. Last week, the UN Security Council called for immediately speeding up aid deliveries, but there has been little sign of change.

US calls for Israel to curb civilian casualties, and international pressure for a cease-fire, have also had little effect.

Israel blames Hamas for the high civilian death toll in Gaza because the militants operate in dense, residential areas. The military says it has killed thousands of militants, without presenting evidence, and that 164 of its soldiers have been killed since the ground offensive began.