DEIR AL-BALAH, Gaza Strip (AP) — Thousands of people have fled Gaza’s largest hospital as Israeli forces and Palestinian militants battle outside its gates, but hundreds of patients, including dozens of babies at risk of dying because of a power blackout, remained inside, health officials said Monday.

With only intermittent communications, it was difficult to reconcile competing claims from the Israeli military, which said it was providing safe corridors for people to escape intense fighting in the north and move south, and Palestinian health officials inside Shifa Hospital, who said the compound was surrounded by constant heavy gunfire.

The military also said it had placed 300 litres (79 gallons) of fuel near the hospital to help power its generators, but that Hamas militants had prevented staff from reaching it. The Health Ministry in Hamas-ruled Gaza disputed that and said the fuel would have provided less than an hour of electricity.

World Health Organization Director-General Tedros Adhanom Ghebreyesus said Shifa has been without water for three days and “is not functioning as a hospital anymore,” in a post on social media.

Another hospital in Gaza City, Al-Quds, was forced to shut down on Sunday because it ran out of fuel. The Palestinian Red Crescent, which operates the facility, said Israeli forces are stationed nearby and that preparations are being made to evacuate some 6,000 patients, medics and displaced people.

Both sides have seized on the plight of hospitals, particularly Shifa’s, as a symbol of the larger war, now in its sixth week. The fighting was triggered by Hamas’ unprecedented October 7 surprise attack into Israel, and Israel’s response has brought unseen levels of death and destruction to Gaza’s 2.3 million Palestinian residents, nearly two-thirds of whom have had to flee their homes with no safe refuge available in the besieged territory.

For Palestinians, Shifa evokes the suffering of civilians. Thousands of people displaced by airstrikes that have destroyed entire city blocks have sought shelter in its darkened corridors. Doctors running low on supplies perform surgery there on war-wounded patients, including children, without anaesthesia.

Israel says the hospital is the prime example of its allegation that Hamas uses human shields, claiming that the militants have a command centre and other military infrastructure in and beneath the medical compound. It has not provided photos or videos to back up these claims. Hamas and hospital staff deny them.

Mohammed Zaqout, the director of hospitals in Gaza, says there are about 650 patients and critically wounded people in Shifa being treated by around 500 medical staff. He estimated that around 2,500 displaced Palestinians are sheltering inside hospital buildings.

On Saturday, the Health Ministry estimated that some 3,000 medics and patients, as well as 15,000 to 20,000 displaced people, were sheltering there.

A UN health official said many displaced families and patients with moderate injuries fled Shifa as Israeli forces encircled the hospital over the weekend. The official, who spoke on condition of anonymity because they were not authorised to brief reporters, said most of the remaining patients could only be relocated with ambulances and other special procedures.

It’s unclear where they would go, as several hospitals and clinics in Gaza have been forced to shut down, while others are already working at full capacity with dwindling supplies.

The Health Ministry said 20 patients, including three babies, have died since the hospital’s emergency generator ran out of fuel on Saturday. It said another 36 babies and other patients are at risk of dying because there is no way to power life-saving medical equipment.

The military said troops would assist in moving babies out of Shifa on Sunday, without saying how it would transport them or where they would be relocated. There was no indication Monday that any had been moved.

Medical Aid for Palestinians, a UK-based charity that has supported Shifa’s neonatal intensive care unit, said transferring critically ill infants is complex. “With ambulances unable to reach the hospital … and no hospital with capacity to receive them, there is no indication of how this can be done safely,” CEO Melanie Ward said. She said the only option was to pause the fighting and allow in fuel.

Christos Christou, the president of international aid group Doctors Without Borders, told CBS’ “Face the Nation” it would take weeks to evacuate the patients.

The US has pushed for temporary pauses that would allow for wider distribution of badly needed aid to civilians in the territory, where conditions are increasingly dire.