Nearly four weeks after Hamas' deadly rampage in Israel sparked the war, US Secretary of State Antony Blinken was heading to the region for talks Friday in Israel and Jordan following President Joe Biden's suggestion for a humanitarian “pause” in the fighting. The aim would be to let in aid for Palestinians and let out more foreign nationals and wounded. Around 800 people left over the past two days.

Israel did not immediately respond to Biden's suggestion. But Prime Minister Benjamin Netanyahu, who has previously ruled out a cease-fire, said Thursday: “We are advancing … Nothing will stop us.” He vowed to destroy Hamas rule in the Gaza Strip.

An airstrike Thursday smashed a residential building to rubble in the Bureij refugee camp several miles south of Gaza City.

One boy, his face covered in blood, cried as workers dug him out of the dirt and wreckage. Others rushed wounded men and women, covered in dust, away on stretchers or wrapped in blankets. At a nearby hospital, doctors tried to stanch the flow of blood from the head of a child laid out on the floor.

At least 15 people were killed, Gaza's Civil Defense spokesperson said, and residents said dozens more were believed buried. The strike took place in the southern zone where Israel has told residents of the north to flee.

Blinken's visit will unfold as Arab countries, including those allied with the US and at peace with Israel, have expressed mounting unease with the war. Jordan recalled its ambassador from Israel and told Israel's envoy to remain out of the country until there's a halt to the war and the “humanitarian catastrophe” it is causing.

A flurry of heavy explosions raised clouds of smoke over Gaza City on Thursday. Al Jazeera television, which continues to broadcast from the city, said Israeli airstrikes were hitting an area of apartment towers in the Tel al-Hawa neighbourhood.

The barrage hit around 100 metres (yards) from Al-Quds Hospital, the Palestinian Red Crescent Society said in post on X. It said there were deaths and injuries but gave no more details.

There was no immediate comment by the Israeli military on the strikes. Israel says it targets Hamas fighters and infrastructure and that the group endangers civilians by operating among them and in tunnels under civilian areas.

The US pledged unwavering support for Israel after Hamas militants killed hundreds of men, women and children on Oct 7 and took some 240 people captive.

But the Biden administration has pushed for Israel to let more aid into Gaza amid growing alarm in the region over the destruction and humanitarian crisis in the tiny Mediterranean enclave.

More than 3,700 Palestinian children have been killed in 25 days of fighting — more than six times the 560 children that the UN has reported killed in 19 months of war in Ukraine as of Oct 8. Bombardment has driven more than half the territory's 2.3 million people from their homes. Food, water and fuel are running low under Israel's siege, and overwhelmed hospitals warn they are on the verge of collapse.

Israel has allowed more than 260 trucks carrying food and medicine through the crossing, but aid workers say it's not nearly enough. Israeli authorities have refused to allow fuel in, saying Hamas is hoarding fuel for military use and would steal new supplies.

White House national security spokesman John Kirby said the US was not advocating for a general cease-fire but a “temporary, localized” pause.

Israel and the US seem to have no clear plan for what would come next if Hamas rule in Gaza is brought down — a key question on Blinken's agenda on his upcoming visit, according to the State Department.

Earlier in the week, Blinken suggested that the Palestinian Authority govern Gaza. Hamas drove the authority's forces out of Gaza in its 2007 takeover of the territory. The authority now holds limited powers in some parts of the Israeli-occupied West Bank.

Military officials said Israeli forces had completely encircled Gaza City, a densely packed cluster of neighbourhoods that Israel says is the centre of Hamas military infrastructure and includes a vast network of underground tunnels, bunkers and command centres.

Israeli forces are “fighting in a built-up, dense, complex area," said the military's chief of staff, Herzi Halevy.

Military spokesman Brig Gen Daniel Hagari said Israeli forces were in “face to face” battles with militants, calling in airstrikes and shelling when needed. He said they were inflicting heavy losses on Hamas fighters and destroying their infrastructure with engineering equipment.

Casualties on both sides are expected to rise as Israeli troops advance toward the dense residential neighbourhoods of Gaza City.

On Thursday, Israeli planes dropped leaflets warning residents to immediately evacuate the Shati refugee camp, a densely built-up district on the Mediterranean coast bordering Gaza City's centre.

“Time is up,” the leaflets read, warning that strikes “with crushing force” against Hamas fighters were coming.

Hundreds of thousands of Palestinians remain in the path of the fighting in northern Gaza, despite Israel's repeated calls for them to evacuate to the south, which is also being bombarded. Many have crowded into UN facilities, hoping for safety.?