Israel said its military launched a “targeted” operation against Hamas early Wednesday morning inside Gaza’s largest hospital, where thousands of Palestinians are believed to be sheltering. Conditions at Al-Shifa Hospital, which has run out of fuel and is no longer considered operational, have deteriorated rapidly in recent days amid intense fighting, with doctors warning of a “catastrophic” situation for patients, staff and displaced people still inside. Wednesday’s raid sparked international criticism. In a statement posted online, the Israel Defense Forces (IDF) said it had begun “a precise and targeted operation against Hamas in a specified area in the Shifa Hospital.” Khader Al-Za’anoun, a reporter for the Palestinian news agency Wafa, described scenes of heavy fighting to CNN. “Explosions are shaking the buildings of Al-Shifa Hospital … which is besieged from all four directions, following the launching of rocket and artillery shells in the vicinity of the hospital,” he said in a text message. Al Za’anoun said Israeli forces had “invaded the hospital with large numbers of soldiers and military vehicles, including tanks, armored vehicles, troop carriers, and bulldozers,” adding they were preventing anyone from leaving. A senior Israeli defense official, speaking with journalists earlier on Wednesday, said Israeli soldiers were in the buildings “conducting search and interrogation operations with the young men amidst intense and violent gunfire inside the hospital.” He added that the Israeli army “is calling on the young men through megaphones to raise their hands, come out, and surrender themselves.” Hamas’ government media office has since claimed that Al-Shifa is under the control of Israeli forces. “We hold the Israeli occupation fully responsible for the lives and safety of medical personnel, the wounded, the sick, premature children, and the displaced,” it said in a statement. However, IDF spokesperson Daniel Haggard said later, in his daily briefing Wednesday, that the military operation at the hospital was “still underway and will take time.” “It’s a complicated area, which still has many people. We need to conduct (it) in the right pace,” he said. Israeli radio said in a report earlier in the day that the army has so far found no indication of hostages inside the hospital. But in a briefing delivered almost 12 hours into the raid, a senior Israeli defense official said soldiers had uncovered weapons at the hospital, and the IDF later released a statement saying it had found an “operational command center” belonging to Hamas in one of the hospital’s departments. Hamas dismissed the claim as a “blatant lie and cheap propaganda.” CNN is trying to contact the hospital to speak to doctors there, but phone calls are not going through. Mark Regev, senior advisor to the Israeli Prime Minister, told CNN’s Wolf Blitzer on Wednesday that more information that he says justifies the IDF’s operation in the hospital would be released “in the coming hours and days.” “The operation is still ongoing and we’ve released some preliminary information, but more will come,” Regev said. Israel is under significant international pressure to prove its claims about Hamas’ infiltration of the hospital, in order to justify some of its military decisions, which could otherwise constitute a possible serious violation of international humanitarian law. There is no indication yet that troops have uncovered a multi-level tunnel structure with underground chambers of the kind illustrated in an animation presented by the army spokesman at a briefing almost three weeks ago. Israel accuses Hamas of using the large hospital complex for military purposes which, it claimed in a statement Wednesday, “jeopardizes the hospital’s protected status under international law.” Hamas and hospital officials have consistently rejected Israel’s claims that Hamas has built a command center under the hospital. Hours before the raid, the White House and the Pentagon said Hamas is storing weapons and operating a command center from the hospital. The Pentagon said the US has newly declassified intelligence that claims to show that Hamas and the Palestinian Islamic Jihad were using hospitals — including Al-Shifa — as a “way to conceal and support their military operations and hold hostages.” However, John Kirby, a National Security Council spokesman said later that Washington had not signed-off on the specific operation around Al-Shifa Hospital and nor did it approve any of Israel’s military plans. It was “not a focus” of US President Joe Biden’s phone call on Tuesday with Israeli Prime Minister Benjamin Netanyahu, Kirby said. He reiterated that the US believes Israel should not target hospitals in Gaza from the air and that civilians should be protected from the crossfire. Human rights bodies fiercely condemned Israel’s raid on Al-Shifa, as the World Health Organization and Palestinian health officials warned they have lost communication with staff inside the hospital. International pressure on the Israeli government has hardened in recent days amid accounts of dire circumstances at Gaza’s other fuel-starved hospitals, and severe shortages of food and water. On Wednesday, the UN Security Council approved a resolution calling for “humanitarian pauses and corridors” in Gaza, in what amounted to a long-awaited diplomatic breakthrough after weeks of bitter negotiations. Twelve countries voted to approve the measure, with the United States, the United Kingdom, and Russia abstaining. The United Nations’ Emergency Relief Coordinator Martin Griffiths said he was “appalled by reports of military raids in Al-Shifa hospital in Gaza.” “The protection of newborns, patients, medical staff and all civilians must override all other concerns. Hospitals are not battlegrounds,” Griffiths said on the platform X, formerly known as Twitter. Meanwhile, the Ramallah-based Palestinian Minister of Health, Mai Al-Kaila, said the Israeli military’s “storming” of Al-Shifa was a “crime against humanity”; the Jordanian Ministry of Foreign Affairs called it “a violation of international humanitarian law”; and Qatar described it as “a war crime and a blatant violation of international laws.” 30-minute warning The IDF said in a statement on Wednesday that it had warned for weeks that Hamas’ “continued military use of the Shifa hospital jeopardizes its protected status.” It said it had also notified the relevant authorities on Tuesday that all military activities within the hospital must stop within 12 hours. But a doctor inside Al-Shifa told CNN they were given just 30 minutes’ warning before the Israeli operation began. “We were asked to stay clear of the windows and the balconies. We can hear the armored vehicles, they are very close to the entrance of the complex,” Dr. Khaled Abu Samra said. Neonatal babies in Al-Shifa hospital are in “severe danger” as conditions deteriorate further, Gaza hospitals director general Zaqout said. “On evacuating the hospital…we have said numerous times there is no place to move 40 incubators outside the hospital,” Zaqout said. CNN could not independently confirm his assessment of the situation. But CNN previously reported on pictures released by Al-Shifa that showed newborn babies taken off failed incubators and wrapped in foil in a desperate bid to keep them alive after oxygen supplies ran out. Hundreds of staff and patients are still inside Al-Shifa, according to the most recent reports from the hospital, along with several thousand who have sought shelter from Israel’s air and ground offensive. The Israeli statement said, “The IDF is conducting a ground operation in Gaza to defeat Hamas and rescue our hostages. Israel is at war with Hamas, not with the civilians in Gaza.” A statement from Hamas blamed both Israel and the United States for the Israeli army raid on the hospital. By supporting what it called Israel’s “false narrative” – that Hamas was using Al-Shifa as a command and control base – it said the US had given Israel, “a green light … to commit more massacres against civilians.” Israel declared war on Hamas, the Palestinian militant group that controls Gaza, and launched a “complete siege” of the enclave following Hamas’ terror attacks in Israel on October 7. An estimated 1,200 people were killed in Hamas’ attacks, and about 240 taken hostage, most of whom remain captive in Gaza. Since then, the Israeli response has killed at least 11,255 Palestinians – including 4,630 children – according to the Palestinian Health Ministry in Ramallah, which draws on medical sources in Gaza. ‘Screams of older people and cries of children’ People inside Al-Shifa have lost contact with other buildings in the complex, jeopardizing efforts by humanitarian workers and Palestinian officials to receive updated information about the catastrophic conditions faced by terrorized patients and medical staff. Omar Zaqout, the supervisor of the ER department, said people were sheltering inside the buildings and staying away from windows and doors. “We don’t know what is going on outside, all we’re hearing are explosions, gunfire, screams of older people and cries of children,” Zaqout added. He said Israeli soldiers were present in buildings around the ER and that he had earlier witnessed people handcuffed, stripped from their clothes and blindfolded. CNN is not on the ground and cannot independently verify his account. CNN has also reached out to the IDF for comment on these allegations but has yet to hear back. Zaqout, the director general of hospitals in Gaza, alleged the IDF interrogated medical teams, patients and their escorts. “Some of the escorts were forced to take their clothes off,” said Zaqout, who is not at the hospital but spoke to the doctors inside. IDF spokesman Rear Admiral Daniel Hagari claimed Israeli forces “include medical teams and Arabic speakers, who have undergone specified training to prepare for this complex and sensitive environment with the intent that no harm is caused to the civilians.” CNN cannot verify Hagari’s claims. For his part, Zaqout insisted that all the people inside the hospital are civilians. “The situation is currently horrific.” Earlier this week, doctors and journalists described desperate efforts to keep premature babies alive and limited procedures taking place by candlelight, as food, milk and water runs out. Hospital director Mohammad Abu Salmiya told Al Jazeera there are plans to bury more than 150 bodies, but he was worried the grave would not be large enough. Al-Za’anoun, the Wafa reporter told CNN, “the smell of dead people is unbearable, most of the bodies are of women and children.” In recent days, 15 patients have died at Al-Shifa, among them six newborns, due to power outages and a shortage of medical supplies, according to the Palestinian Ministry of Health in Ramallah, which draws its figures from the Hamas-controlled territory. Egyptian health minister Khaled Abdel Ghaffar said Tuesday they are working to bring 36 newborns from Al-Shifa to Egypt, though such a transfer would be dangerous. The World Health Organization has recorded at least 137 attacks on health facilities in Gaza, which it said resulted in 521 deaths and 686 injuries. Other protected sites, like schools, civilian shelters, and United Nations facilities have already been damaged or destroyed in over a month of Israeli airstrikes. On Monday, the United Nations Relief and Works Agency for Palestine Refugees (UNRWA) announced that over 100 UN staffers had been killed in Gaza since fighting began – the most in the United Nation’s history. This is a developing story and is being updated.