The health ministry in Hamas-run Gaza said Friday that Israeli forces had detained hundreds of staff, patients and displaced people during a raid on the last functioning hospital in the north of the territory.
The Israeli military said its forces were operating around Kamal Adwan Hospital in the Jabalia refugee camp in north Gaza, where it launched a major operation earlier this month.
The operation has sparked fresh concerns about the war's civilian toll, with UN rights chief Volker Turk saying the conflict's "darkest moment" was currently unfolding in northern Gaza.
The World Health Organization said it had lost contact with staff at the hospital since Friday morning.
"This development is deeply disturbing given the number of patients being served and people sheltering there," WHO chief Tedros Adhanom Ghebreyesus said.
Gaza's health ministry said Israel's forces "stormed" the hospital, "detaining hundreds of patients, medical staff and some displaced individuals from neighbouring areas who sought refuge".
Israel's COGAT defence ministry body said it had allowed the transfer of 23 patients out of the hospital on Thursday night, which was confirmed by the WHO.
Rik Peeperkorn, the WHO representative for the Palestinian territories, said he witnessed "mayhem and chaos" at the hospital on Thursday night.
At a checkpoint close to the hospital, the visiting WHO team saw "thousands of women and children leaving that area, walking, limping with their few belongings" towards Gaza City, he added.
- 'Rocket fell next to us' -
UN rights chief Turk pointed out that already "more than 150,000 people are reportedly dead, wounded or missing in Gaza" since the war broke out just over a year ago.
That number could "rise dramatically", he said, warning that Israel's policies in northern Gaza "risk emptying the area of all Palestinians".
"We are facing what could amount to atrocity crimes, including potentially extending to crimes against humanity."
The Israeli military says the goal of the assault is to destroy the operational capabilities it says Hamas is trying to rebuild in the north.
Also in northern Gaza on Friday, Gaza's civil defence agency said Israeli drone strikes killed 12 people waiting to receive aid near the Al-Shati refugee camp.
There was no immediate comment from the military.
In the south Gaza city of Khan Yunis, 14 people including nine children were killed in an Israeli strike that hit the Fara family home, the civil defence agency's Mahmud Bassal said.
"The rocket fell next to us, and we were buried under the rubble," Umm al-Ameer al-Fara, who survived the first strike, told AFP.
"My children and sister were killed."
A separate strike in Khan Yunis killed six people, Bassal said.
The Israeli military said "a number of terrorists were eliminated" in south Gaza.
- Three journalists killed -
Hamas's October 7, 2023 attack which triggered the Gaza war resulted in the deaths of 1,206 people in Israel, mostly civilians, according to an AFP tally of Israeli official figures.
Israel's retaliatory campaign in Gaza has killed 42,847 people, the majority civilians, according to figures from the Hamas-run territory's health ministry which the United Nations considers reliable.
After a nearly a year of rocket fire by the Iran-backed militant group Hezbollah, a Hamas ally, Israel expanded its focus to Lebanon last month in a bid to secure its northern border.
At least 1,580 people have been killed in Lebanon since all-out war erupted on September 23, according to an AFP tally of Lebanese health ministry figures.
The Israeli military has announced the deaths of 32 soldiers since it began ground operations in Lebanon late last month.
On Friday, Lebanon accused Israel of a "deliberate" attack that killed three journalists.
Asked by AFP for comment on the strike, the Israeli military has not yet responded.
Pro-Iran Lebanese television channel Al Mayadeen said cameraman Ghassan Najjar and broadcast engineer Mohammad Reda were killed in the strike on a journalists' residence in the southern town of Hasbaya.
Another TV outlet, Al-Manar, run by Hezbollah, said video journalist Wissam Qassem was also killed in the strike on a bungalow located in a complex that several media organisations covering the war had rented out.
- Border crossing hit -
Journalists from other media organisations were also sleeping nearby when the strike hit, in an area outside Hezbollah's traditional strongholds.
"I woke up to the whistling sound of a missile and found my door burst open... I thought there was a fire," Sky News Arabia correspondent Darine El Helwe told AFP.
Lebanon's Prime Minister Najib Mikati said the "deliberate" attack was among the "war crimes committed by the Israeli enemy".
Falling shrapnel from rockets fired by Hezbollah killed two people in the Arab town of Majd al-Krum in northern Israel, a hospital and the Israeli army said.
Hezbollah had earlier said it sent "a large rocket salvo" targeting a nearby city.
The armed group also said it hit three Israeli tanks in clashes in two villages near the border.
The Israeli military meanwhile confirmed it struck a northern border crossing between Lebanon and Syria, accusing Hezbollah of moving weapons through it.
The UN refugee agency warned that the crossing had been the main escape route for people trying to flee the conflict in Lebanon.
"This is hindering and really putting at risk a main lifeline," the UNHCR's Rula Amin said.
More than half a million people, mostly Syrians, have crossed over into Syria since the conflict began last month, Lebanese authorities said.