A fresh wave of Israeli strikes across Gaza has killed 53 Palestinians, according to local health authorities, as Israel signalled a major escalation in military operations in the strip and plans to seize land.
Gaza's health ministry said children were among 19 dead after an attack on a clinic run by the United Nations' Palestinian aid agency UNRWA, where people were sheltering in Jabalia in Gaza's north.
The Israel Defense Forces (IDF) said Hamas was using the clinic as a command centre — an allegation Hamas said was a "blatant fabrication."
Bodies were lined up at the Indonesian Hospital in nearby Beit Lahiya, with video showing one man carrying what he said were the remains of a one week old baby girl.
The latest strikes across Gaza followed an announcement by Israeli defence minister Israel Katz that troops would begin to clear areas of Hamas terrorists and infrastructure "and seize large areas that will be added to the security zones of the State of Israel".
"We are now cutting off the strip and we are increasing the pressure step by step, so that [Hamas] will give us our hostages," Prime Minister Benjamin Netanyahu said in a video statement.
"And the more they do not give, the more the pressure will increase until they do."
There are 59 Israeli hostages still held in Gaza — 24 believed to still be alive, while 35 have been declared dead by Israeli authorities.
But it will also inflame the dire humanitarian situation across the war-ravaged strip, much of which had been reduced to rubble since the war began after Hamas' deadly attacks on Israel on October 7 2023.
The Palestinian death toll in the 18 months since the conflict began stands at more than 50,000.
There has been intense fighting in southern Gaza over the last week, including around Tel al-Sultan where 15 Palestinian medics and emergency responders were killed when the IDF opened fire on their convoy.
After earlier refusing to answer questions about why their bodies and the wreckage of their vehicles were buried, an IDF official has confirmed to the ABC that troops covered the remains under "sand and cloth sheets".
The official claimed it was done while the recovery mission with the UN and the Palestinian Red Crescent was coordinated.
Palestinians displaced again
The Israel Defense Forces (IDF) had issued evacuation warnings for large swathes of southern Gaza the day before it announced it would intensify its operations.
Some estimates suggested more than 100,000 people were told to leave areas around Rafah and Khan Younis, and move to the "humanitarian" zone further north in Al Mawasi.
Rifat Ismail Al Tartouri, 62, and his family were among those who had fled Tel al-Sultan, setting up camp further in to Khan Younis.
"The situation was very difficult — my mother is 90, my son had to carry her on his shoulder," he told the ABC.
"There are no cars, there is no petrol, nothing.
"People are walking on main roads with airplanes over their heads."
Nearby, 38-year-old Hadil Shaat was helping set up a tent for her family.
"We came to Khan Younis because we were told to leave Rafah, we do not know where to be protected or how to protect ourselves," she said.
"By leaving Rafah we feel that we won and we are away from death, it is a big thing that we ran away."
Israeli moves 'characteristic' of annexing Gaza
Mr Katz's announcement did not detail how much land the IDF would seek to seize, how it would be controlled, or how many troops would be involved.
But it sparked concerns the Netanyahu government was again breaching international law.
"It's the language really of annexation that's really most troubling about this," Don Rothwell, professor of international law at the Australian National University said.
"Israel is a legitimate occupying power in Gaza that's consistent with the fourth Geneva Convention.
"But under the Geneva Convention, Israel cannot seek to seize and certainly annex the territory of lands that it is occupying.
"So this announcement certainly has all of the characteristics of effectively an annexation of parts of Gaza."
Israel's actions in annexing and controlling land had been reviewed by international courts multiple times, with the International Court of Justice issuing an opinion in July last year that its occupation of the Palestinian Territories as illegal.
"There's really a track record in terms of Israeli conduct in this regard, but I think it's fair to say that this is the first instance of this type of conduct since the outbreak of hostilities between Israel and Hamas in October 2023," he said.
"We are in a twilight zone with respect to Israel's adherence to international law, and of course the Trump administration, as we know, is very actively backing Israel on these matters.
"But it also needs to be observed that we know that the International Criminal Court is consistently reviewing Israel's conduct in terms of its activities in Gaza — and violations such as this, extreme violations of the Fourth Geneva Convention, may well provide a basis for further expansion of ICC investigations into the conduct of Israel's politicians in this regard."
Days before Israel resumed its bombardment of Gaza on March 18, Israel-based human rights watchdog Gisha calculated that Israel was already in control of around 62 square kilometres or 17 per cent of the territory.
Under the January ceasefire agreement, Israeli forces had withdrawn to a strip of land along the Israel-Gaza border.
The area, 700 metres to 1 kilometre wide in parts, is referred to as a "buffer zone" — with Israel insisting it was required to protect border communities.
Prime Minister Benjamin Netanyahu announced that as part of the expanded campaign, a new military area would be created — known as the Morag corridor.
It would be a few kilometres north of the existing Philadelphi corridor, which is the name given the strip of land running along the Gaza-Egypt border and which has been under Israeli control since last year.
Former hostage warns of dire consequences of fresh fighting in Gaza
Former hostage Romi Gonen, who was one of the three Israelis freed in the hours after the former ceasefire came into force on January 19, voiced her fears about what the surge in military operations would mean for hostages still in Gaza.
"It's a difficult morning with the expansion of fighting in Gaza," she posted on Instagram.
"Every explosion crushes the hope of the hostages.
"I was there. I know."
The Hostages and Missing Families Forum said the families of those still held captive were "horrified" at the Israeli defence minister's announcement.
"The Israeli government has an obligation to free all 59 hostages from Hamas captivity — to pursue every possible channel to advance a deal for their release," the group said in a statement.
"Every day that passes puts our loved ones in captivity at greater risk of death at the hands of the murderous terrorist organisation Hamas.
"Their lives hang in the balance as more and more disturbing details continue to emerge about the horrific conditions they're being held in — chained, abused, and in desperate need of medical attention."
One former hostage, Eliya Cohen has detailed his treatment in captivity in an interview with Israeli television Channel 12.
He said he was chained for months at a time, and food only increased in the month before he was released.
