Palestinians said deadly strikes on Friday hit hospitals and a school where desperate civilians in Gaza City have sought refuge from intense combat that has sent thousands of others fleeing.
The Israeli army has repeatedly accused Palestinian militant group Hamas of using hospitals, particularly Al-Shifa, to coordinate their attacks and also as hideouts for its commanders. Hamas authorities deny the accusations.
"There is no safe place left. The army hit Al-Shifa. I don't know what to do," said 32-year-old Abu Mohammad, who was among those seeking refuge at the hospital. "There is shooting... at the hospital. We are afraid to go out."
Al-Shifa's director and Gaza's Hamas government, which reported a death toll of 13, blamed Israeli forces for a strike on the hospital.
The hospital received the bodies of another 50 people killed in a strike on Gaza City's Al-Buraq school, the Al-Shifa director said.
The Palestinian Red Crescent Society said Israeli snipers had also shot at Al-Quds hospital, killing at least one person.
Israeli forces would "kill" Hamas militants if they saw them "firing from hospitals", military spokesman Richard Hecht said.
Heavy fighting was raging near Al-Shifa hospital, with Israel saying it had killed dozens of militants and destroyed tunnels that are key to Hamas's capacity to fight.
"Last night, I wasn't optimistic that any of my children or I would come out unharmed, given the intensity of the bombing and gunfire," said Jawad Haruda, who was among thousands walking south in an exodus away from Gaza City.
"We couldn't wait for the morning, and everyone in Al-Shifa hospital left," he added.
Witnesses told AFP that hundreds of people sheltering at Gaza City's Al-Rantisi hospital fled on instruction from the Israeli military, which was surrounding it with armoured vehicles.
Amid the fighting, the International Committee of the Red Cross warned the health system in the Gaza Strip had "reached a point of no return".
In Israel, medical services reported two women were wounded in rocket attacks in Tel Aviv. Hamas's military wing said it had targeted the Israeli commercial hub.
The war in the densely populated coastal territory, which is effectively sealed off, has prompted repeated calls for a ceasefire to protect civilian lives and allow in more humanitarian aid.
Tens of thousands of people have fled to the south of the territory in recent days, often on foot and with only the things the could carry.
Almost 1.6 million people have been internally displaced since October 7, the UN agency for Palestinian refugees (UNRWA) said -- nearly two thirds of Gaza's population.
But the UN estimates hundreds of thousands of civilians remain in the fiercest battle zones in the north.
The United Nations called for an end to the "carnage" in Gaza, saying "razing entire neighbourhoods to the ground is not an answer for the egregious crimes committed by Hamas".
"To the contrary, it is creating a new generation of aggrieved Palestinians who are likely to continue the cycle of violence. The carnage simply must stop," UNRWA chief Philippe Lazzarini wrote in an opinion piece.
Lazzarini also said on social media that over 100 UNRWA colleagues were confirmed killed in one month of war, noting the figure included parents, teachers, nurses, doctors and support staff.
"Enough destruction, there's nothing left. We need a truce to see what will later happen to us, a truce to bring medicine or aid to the hospitals," said Mohammed Khader, who was displaced in Rafah.
"Those hospitals are now full of displaced people and not only injured and martyrs," he added.
Israeli Prime Minister Benjamin Netanyahu has repeatedly rejected halting the fighting.
Complicating Israel's military push is the fate of the hostages abducted on October 7.
Four hostages have been freed so far by Hamas and another released in an Israeli operation. The desperate relatives of those still held in Gaza have piled pressure on Israeli and US authorities to secure the release of their loved ones.
The conflict has also stoked regional tensions, with cross-border exchanges between the Israeli army and Lebanon's Hezbollah, and Yemen's Huthi rebels saying they launched "ballistic missiles" at southern Israel.
Iran's Foreign Minister Hossein Amir-Abdollahian said the expansion of the Israel-Hamas war has become "inevitable".
Saudi Arabia is hosting Arab leaders and Iran's president for two summits this weekend in emergency meetings of the Arab League and the Organisation of Islamic Cooperation.
Saudi Arabia's Crown Prince Mohammed bin Salman denounced the conduct of Israeli forces in Gaza, saying "we stress the necessity of stopping this war and forced displacement".
US Secretary of State Antony Blinken wrapped up a marathon diplomatic push Friday, saying Israel's pauses in its Gaza offensive would "save lives" but more was needed.
"Far too many Palestinians have been killed," Blinken said in New Delhi, his last stop before heading home, where he repeated US support for ally Israel but was firm that more aid had to reach civilians in Gaza.