Gaza was under "unprecedented bombardment" from Israel, Palestinian news agency WAFA reported, while Palestinian telecommunications company Paltel said that all communications and internet services had once again been cut.
Palestinian Authority President Mahmoud Abbas joined international calls for an immediate ceasefire at a meeting with US Secretary of State Antony Blinken, who was making an unannounced visit to the occupied West Bank.
But after Blinken repeated US concerns that a ceasefire could aid Hamas, Israeli Prime Minister Benjamin Netanyahu ruled that out unless hostages held by Hamas were released: "There will be no ceasefire without the return of the hostages. This should be completely removed from the lexicon."
Tensions increased with Lebanon as an Israeli strike on a car in the south of the country killed three children and their grandmother, Lebanese authorities said.
Israel's chief military spokesperson said the military had attacked "terrorist targets of Hezbollah in southern Lebanon" in response to a missile attack against tanks that killed an Israeli citizen. He said a Hezbollah drone was also shot down.
Sirens have sounded across central Israel, with Israeli media reporting rockets struck areas in and around Tel Aviv. No casualties were reported.
Gaza health officials said more than 9,770 Palestinians have been killed in the war, which began when Hamas launched a surprise attack on southern Israel on October 7, killing 1,400 people and taking more than 240 hostage.
Israel said 31 of its soldiers have been killed so far.
At the Maghazi refugee camp in Gaza, where the health ministry in the Hamas-run enclave said Israeli forces had killed at least 47 people in an overnight strike, people searched for victims or survivors.
"All night I and the other men were trying to pick the dead from the rubble. We got children, dismembered, torn-apart flesh," said Saeed al-Nejma, 53, adding that he had been asleep with his family when the blast hit his neighbourhood.
In a separate attack, 21 Palestinians from one family, including women and children, were killed in strikes overnight, the health ministry said. The IDF declined to comment.
Reuters could not independently verify these accounts.
"We demand that you stop them from committing these crimes immediately," Abbas told Blinken, urging an "immediate ceasefire" from Israel.
"There are no words to describe the war of genocide and destruction to which our Palestinian people are being subjected in Gaza at the hands of the Israeli war machine, without regard to the rules of international law," news agency WAFA quoted Abbas as telling Blinken.
Ceasefire calls
Foreign ministers from Qatar, Saudi, Egypt, Jordan and the United Arab Emirates met Blinken in Amman on Saturday and also urged him to persuade Israel to agree to a ceasefire.
Pope Francis joined calls for peace. "Stop in the name of God," he said, calling for humanitarian aid and help for the injured to ease the "very grave" situation in Gaza.
But Blinken says a ceasefire would benefit Hamas, allowing it to regroup and attack again. Instead, the US wants localised pauses in fighting to allow in humanitarian aid and for people to leave Gaza.
"The Secretary reaffirmed the United States' commitment to the delivery of life-saving humanitarian assistance and resumption of essential services in Gaza," spokesperson Matthew Miller said.
Blinken said the Palestinian Authority should play a central role in the future of the Gaza strip, a US official said after the West Bank visit.
Evacuations halted
Efforts were under way on Sunday to resume evacuations of foreign nationals and injured Gazans through the Rafah crossing to Egypt, suspended since Saturday after a deadly attack on an ambulance, Egyptian, US and Qatari officials said.
The Rafah crossing to Egypt's Sinai peninsula is the only exit point from Gaza not controlled by Israel. Aid trucks were still able to travel into Gaza, two Egyptian sources said.
Evacuations began on Wednesday under an internationally brokered deal. More than 300 Americans have left Gaza, but some remain, Jonathan Finer, deputy national security adviser, said.
Qatar's foreign ministry said that without a "period of calm" in Gaza its mediators would not be able to secure the release of Israeli hostages held in the enclave.
The Gulf state has, in coordination with the US, led talks with Hamas and Israeli officials over the release of hostages.
Worsening violence in the Israeli-occupied West Bank has fuelled concerns it could become a third front in a wider war, in addition to Israel's northern border with Lebanon.
Israeli military spokesperson Rear Admiral Daniel Hagari said the IDF were focussing on ground operations in the north of Gaza "to free our hostages and to free Gaza from Hamas".
"We will adapt our plan to stay with the goals, and it will take us a long time," he added.
He said the IDF has exposed a network of Hamas tunnels, command centres and rocket launchers beneath and adjacent to hospitals in northern Gaza.
"Hamas systematically exploits hospitals as part of its war machine," Hagari told reporters.
In a statement, Hamas called on the United Nations secretary general to form an international committee to visit hospitals to counter Israel's "false claims" that Hamas uses them to launch attacks
The U.N. humanitarian office estimates that nearly 1.5 million of Gaza's 2.3 million people are internally displaced.
Aid currently entering Gaza is "nowhere near" enough to meet people's needs, World Food Programme head Cindy McCain said after visiting the Rafah crossing.
"People are living in a horrific nightmare," McCain said. "Food and water are running out. A steady flow of aid is needed to meet the desperate needs now."
In southern Turkey, police used tear gas and water cannon as hundreds of people at a pro-Palestinian rally tried to storm an air base that houses US troops, hours before Blinken was due in Ankara for talks on Gaza on Monday.
