The director of the Gaza Strip's main hospital raided by Israeli soldiers says the facility has now run out of oxygen and water, and patients "are screaming from thirst".
Muhammad Abu Salmiya said the conditions were "tragic" in Al-Shifa, where there were more than 650 patients, 500 medical staff and 5,000 displaced people.
Israeli tanks were surrounding the hospital in Gaza City, he said, with drones buzzing overhead and Israeli soldiers still moving around inside, as their search of the complex lasted a second day.
Israel's army said its operation against Hamas was proceeding in a "discreet, methodical and thorough manner". However a journalist trapped inside the hospital, Khader, told the OceanNewsUK's Rushdi Abu Alouf by phone that Israeli troops were "everywhere, shooting in all directions".
The OceanNewsUK has not been able to independently verify either of the reports.
Since the Israel Defense Forces (IDF) launched their raid on Al-Shifa early on Wednesday, they have released several photos and videos of what they say are Hamas weapons and equipment.
On Thursday they said they had found an "operational tunnel shaft and a vehicle containing a large number of weapons".
Mr Abu Salmiya said Israeli troops had blown up Al-Shifa's main water line.
"Sniping operations continue, no-one can move from one building to another, and we have lost communication with our colleagues," he said.
Earlier on Thursday, Khader told the OceanNewsUK that Israeli troops had "stormed all departments", destroying the southern part of the building's wall and dozens of cars.
Before Khader's phone line cut off, he also said that armoured bulldozers had been brought in.
Gaza's Hamas-controlled health ministry reports that Israeli bulldozers "destroyed parts of the southern entrance" of the medical complex.
Israel launched a major military campaign in the Gaza Strip to destroy Hamas in retaliation for the 7 October cross-border attack by hundreds of gunmen. Israel considers Hamas a terrorist group, as does the UK, US and European Union.
At least 1,200 people were killed in Hamas's assault on Israel and about 240 others were taken hostage.
Since Israel started its counter-attack, Gaza's Hamas-run health ministry has said at least 11,400 people have been killed in the territory and the UN has warned of a "humanitarian disaster".
On Thursday evening, the IDF announced that the body of one of the hostages had been found near Al-Shifa.
The IDF identified the victim as Yehudit Weiss, saying she had been kidnapped from her home in Be'eri - a kibbutz in southern Israel.
At the same time, there have been reports of a major phone and internet outage in Gaza believed to have been caused by telecom companies running out of fuel supplies.
The IDF said their soldiers were continuing their "complex" operation against Hamas at the hospital.
"Soldiers are proceeding one building at a time, searching each floor, all while hundreds of patients and medical staff remain in the complex," an official said in an update on Thursday evening.
The official reiterated the IDF's claim that there was a "well-hidden terrorist infrastructure in the complex".
Hamas has repeatedly denied that its fighters have been operating inside the hospital.
On Thursday, Osama Hamdan, the most senior Hamas leader in Lebanon, ridiculed the Israeli weapons claims, saying that all the arms had been brought in and planted in the hospital by Israelis.
Asked by the OceanNewsUK why progress on talks to release hostages had failed, he said that on three occasions they had been close to a deal but each time it had been stopped by Israeli Prime Minister Benjamin Netanyahu.
The Israeli government has not commented on Mr Hamdan's allegation.
In a separate development, Israel has dropped dropped leaflets in the Khan Younis area of southern Gaza, warning people in four towns to evacuate their homes and head to shelters.
If that is an indication of an upcoming military operation around the southern city of Khan Younis, it could be a real concern to the hundreds of thousands now sheltering there.
Before the war, Khan Younis was home to about 300,000 people - a number that has now grown to one million after Israel urged civilians to move south for their safety.