Tens of thousands of displaced Palestinians have streamed into the overwhelmed town of Rafah in the southernmost end of Gaza in recent days, according to the United Nations, as Israeli forces on Friday continued to blast through dense areas in the centre of the strip, killing dozens of people.

Israel's unprecedented air and ground offensive against Hamas has displaced some 85 per cent of the Gaza Strip's 2.3 million residents, sending swells of people seeking shelter in Israeli-designated safe areas that the military has nevertheless also bombed. That has left Palestinians with a harrowing sense that nowhere is safe in the tiny enclave.

Israel's widening campaign, which has already flattened much of northern Gaza, is now focused on built-up areas in central Gaza, where Israeli warplanes and artillery pounded the urban refugee camps of Bureij, Nuseirat and Maghazi, levelling buildings, residents said.

But fighting is raging across many areas of Gaza. It has not abated in the north, where Hamas is still battling Israeli troops with tough resistance. And the second-largest city of Khan Younis in the south, where Israel believes Hamas' leaders are hiding, is also a smoldering battleground.

The war has already killed over 21,300 Palestinians and sparked a humanitarian crisis that has left a quarter of Gaza's population starving.

Israel has vowed to dismantle Hamas and bring back more than 100 hostages still held by the militants after their October 7 attack on southern Israel. The assault killed some 1,200 people, mostly civilians.

Israeli officials have brushed off international calls for a cease-fire, saying it would amount to a victory for Hamas.

A STREAM OF DISPLACEMENT

The UN said late Thursday that around 100,000 people have arrived in Rafah, along the border with Egypt, in recent days. The influx crams even more people into one of Gaza's most densely populated areas.

Israel has told residents of central Gaza to evacuate and head toward Rafah and the central city of Deir al-Balah. But even as the displaced have poured in, Rafah has not been spared from Israeli attacks.

A strike Thursday evening destroyed a residential building, killing at least 23 people, according to the media office of the nearby Al-Kuwaiti Hospital.

At the hospital, residents rushed in a baby whose face was flecked with dust and who wailed as doctors tore open its Mickey Mouse onesie to check for injuries.

Shorouq Abu Oun fled the fighting in northern Gaza a month ago and sheltered at her sister's house, which is located near Thursday's strike

“We were displaced from the north and came here as they (the Israeli military) said it is safe,” said Abu Oun, speaking at the hospital where the dead and wounded were taken. “I wish we were martyred there (in northern Gaza) and didn't come here.”

The displaced arrived in Rafah in trucks, carts and many on foot. Those who haven't found space in the already overwhelmed shelters have built tents on the roadsides, especially near hospitals.

STRIKES IN CENTRAL GAZA

Residents said Friday many houses were hit overnight across Nuseirat and Maghazi. The registration office at the al-Aqsa Martyrs hospital in Gaza's central city of Deir al-Balah said it received the bodies of 40 people, including 28 women, who were killed in Israeli strikes in central Gaza.

“They are hitting everywhere,” Saeed Moustafa, a Palestinian man from Nuseirat, said of the Israeli military. “Families are killed inside their homes and the streets. They are killed everywhere.”

Heavy fighting was also reported between Israeli troops and the Palestinian militants in Bureij, according to Rami Abu Mosab, a displaced Palestinian from northern Gaza who was sheltering in Bureij.

Israel said this week it was expanding its ground offensive into central Gaza, targeting a belt of crowded neighbourhoods across the region that were built to house some of the hundreds of thousands of Palestinian refugees from the 1948 war surrounding Israel's creation.

Israel says Hamas embeds inside the civilian population and that its forces have uncovered weapons troves and underground tunnel shafts in residential buildings, schools and mosques.

But even Israel's closest ally, the United States, has urged it to take more precautions to spare civilians and allow in more aid. Israel says it warns civilians to leave areas that it is targeting in multiple ways and that it has worked to be more precise in its evacuation orders.

Civilians are bearing a staggering toll in the fighting. On Sunday, an Israeli strike on the Maghazi camp killed at least 106 people, according to hospital records.

In a preliminary review of the incident, the Israeli military said that buildings near the target were also hit during the strikes, which it said “likely caused unintended harm to additional uninvolved civilians.” In a statement Thursday, the military said it regretted the harm to civilians and said it would learn from the incident.

Israel seldom comments on specific strikes and has rarely acknowledged any fault even when civilians are killed.

Israel's offensive in Gaza has already been one of the most devastating military campaigns in recent history. More than 21,300 Palestinians, most of them women and children, have been killed, according to the Health Ministry in Hamas-ruled Gaza. Another 55,600 have been wounded, it says. Those counts do not differentiate between civilians and combatants.

The military says it has killed thousands of militants, without presenting evidence, and that 168 of its soldiers have been killed and hundreds wounded since the ground offensive began in late October.