Tens of thousands of newly displaced Gazans huddled under tarpaulins on Friday in the centre of the Palestinian enclave after fleeing an Israeli tank offensive, while warplanes attacking the south flattened homes and buried families as they slept.
Israel is closing the year with new assaults in central and southern Gaza, unleashing a fresh exodus of people already driven from other areas.
Israeli forces have laid much of the Gaza Strip to waste. Nearly all its 2.3 million people have been driven from their homes at least once, and many are now fleeing for the third or fourth time.
Gaza health authorities said 187 more Palestinians were confirmed killed in Israeli strikes in the past 24 hours, raising the toll to 21,507 - about 1 percent of Gaza's population - with thousands more bodies feared unrecovered in the ruins.
In the south of the Gaza Strip in Rafah, Reuters journalists at the scene of one air strike that obliterated a building saw the head of a buried toddler sticking out of the rubble.
The child screamed as a rescue worker shielded his head with a hand, while another swung a sledgehammer at a chisel, trying to break up a slab of concrete to free him.
Neighbour Sanad Abu Tabet said the two-storey house had been crowded with displaced people. After morning broke, relatives came to collect the dead wrapped up in white shrouds. A man peeled away the cloth to stroke the face of a dead child.
Tens of thousands of Gazans are fleeing the crowded central districts of Bureij, Maghazi and Nusseirat, ordered out by Israeli forces whose tanks advanced from the north and east.
Most have made their way south or west to the already overwhelmed city of Deir al-Balah, pitching makeshift tents made from sheets of plastic on whatever open ground they could find.
"We suffered a lot. We had the whole night without shelter, under rain and it was cold, we were with our kids and elderly women," said Um Hamdi, a woman cooking porridge over an open woodfire, surrounded by children.
Nearby, grey-bearded Abdel Nasser Awadallah stood inside a wooden frame set up to be wrapped in plastic to make a tent, and spoke of the family he had lost.
"I buried my children, a child 16-years-old, another one aged 18. Something I really can't believe, I buried my children at 6am while their bodies were still warm. Also my nephew he was 2-years-old, I buried him, I buried my wife," he said.
"I never thought in my life that I will bury my children, I thought they would bury me."
Israel's closest ally the United States has publicly called this month for it to scale down the full-blown war in coming weeks and transition to targeted operations against Hamas leaders.
But so far Israel shows no sign of doing so, launching a new assault in the final week of the year that began with intense bombing of central areas.
Israel issued a rare apology on Thursday for killing civilians in a huge air strike on Christmas Eve that Palestinian authorities say killed scores of people and triggered one of the biggest exoduses of the war so far.
Residents say Israeli forces have fought their way deep into Bureij in the battle in central Gaza in the past two days, with intense fighting still taking place on the eastern outskirts. Bombing has been particularly intense there, and in adjacent Nusseirat and Maghazi.
Footage filmed by a Palestinian Red Crescent volunteer in Maghazi showed dead and wounded being carried from ruined buildings there. Palestinian media reported strikes in Nusseirat had killed at least 35 people overnight.
In the south, Israeli forces have also been pounding Khan Younis, in preparation for an anticipated further advance into the main southern city, swathes of which they captured in early December.
Gallant, the Israeli defence minister, described Israeli operations there as "a task that has never been done before" and said troops were reaching Hamas command centres and arms depots.
Gaza is almost entirely reliant on food, fuel and medical supplies from the outside, and Israel has shut off all access apart from at the southern edge.
International bodies say supplies being let in through Israeli inspections are a small fraction of the enclave's vast needs. Last week Israel bowed to international pressure to open a second crossing it said would double the number of supply trucks daily to 200, but just 76 were able to enter on Thursday, according to the United Nations, compared to 500 in peacetime.
Israel says it will fight on until it annihilates Hamas. Palestinians say wiping out the group is unachievable because of its diffuse structure and deep roots in a territory it has ruled since 2007.
Israel's Western allies, led by Washington, have defended its right to protect itself by retaliating against Hamas, but have grown increasingly alarmed by the high death toll and humanitarian devastation.
Efforts by mediators Egypt and Qatar to negotiate a ceasefire have so far been fruitless since a week-long truce collapsed at the end of November. Egypt, which hosted the leaders of Hamas and smaller group Islamic Jihad in the past week, said on Thursday it was awaiting responses from the warring sides to a proposed peace plan.