Israel says there will be no humanitarian exceptions to its siege of the Gaza Strip until all its hostages are freed after the Red Cross pleaded for fuel to be allowed in to prevent overwhelmed hospitals from "turning into morgues".
Israel has vowed to annihilate the Hamas movement that rules the Gaza Strip in retribution for the deadliest attack on Jewish civilians since the Holocaust when hundreds of gunmen poured across the barrier fence and rampaged through Israeli towns on Saturday.
Public broadcaster Kan said the Israeli death toll had risen to more than 1300 since Saturday.
Most were civilians gunned down in their homes, on the streets or at a dance party.
Scores of Israeli and foreign hostages were taken back to Gaza - Israel says it has identified 97 of them.
The full scale of the killings has emerged in recent days after Israeli forces reclaimed control of towns, finding homes strewn with bodies.
They say they found women who had been raped and killed and children who were shot and burned.
Israel has responded so far by putting Gaza, home to 2.3 million people, under total siege and launching by far the most powerful bombing campaign in the 75-year history of the Israeli-Palestinian conflict, destroying whole neighbourhoods.
Gaza authorities say more than 1200 people have been killed and more than 5000 people have been wounded in the bombing.
The sole electric power station has been switched off and hospitals are running out of fuel for emergency generators.
The International Committee of the Red Cross said fuel powering emergency generators at hospitals could run out within hours.
"The human misery caused by this escalation is abhorrent, and I implore the sides to reduce the suffering of civilians," ICRC regional director Fabrizio Carboni said in a statement on Thursday.
"As Gaza loses power, hospitals lose power, putting newborns in incubators and elderly patients on oxygen at risk.
"Kidney dialysis stops, and X-rays can’t be taken.
"Without electricity, hospitals risk turning into morgues."
Israeli Energy Minister Israel Katz said there would be no exceptions to the siege without freedom for Israeli hostages.
"Humanitarian aid to Gaza? No electrical switch will be lifted, no water hydrant will be opened and no fuel truck will enter until the Israeli hostages are returned home. Humanitarian for humanitarian. And nobody should preach us morals," Katz posted on social media platform X.
In Gaza's Al Shati refugee camp, residents were sifting through rubble with their bare hands looking for survivors and bodies.
Rescue workers say they lack fuel and equipment to dig victims out of collapsed buildings.
The United Nations says at least 340,000 Gazans have been made homeless in the past four days, with almost 220,000 of them sheltering in 92 UN-run schools.
United States Secretary of State Antony Blinken landed in Israel on Thursday on a trip to show solidarity with Israel, help prevent the war from spreading and push for the release of hostages, including American citizens.
He will also visit Jordan on Friday to meet King Abdullah and Mahmoud Abbas, head of the Palestinian Authority which operates limited self-rule in the Israeli-occupied West Bank.
Abbas, whose Fatah movement lost control of the Gaza Strip to its Hamas rivals in 2007, has not condemned the attacks on Israel, has blamed the escalation on the neglect of Palestinian grievances, and has called for Palestinians outside Gaza to resist the Israeli military.
Israel formed a new unity war government on Wednesday, bringing opponents of Prime Minister Benjamin Netanyahu into his cabinet.
It has called up hundreds of thousands of reservists in preparation for what could be a ground assault on Gaza.
No decision to invade has yet been made "but we're preparing for it", military spokesperson Lieutenant-Colonel Richard Hecht said on Thursday.
The war has torn up diplomacy in the region, just as Israel was preparing to reach an agreement to normalise ties with Saudi Arabia and months after Riyadh resumed ties with its regional rival Iran, sponsor of Hamas.
Tehran has celebrated the Hamas attacks but denied being behind them.
