KHAN YOUNIS, Gaza Strip — The Israeli military entered Gaza’s largest hospital early Wednesday, conducting what it called a “precise and targeted operation against Hamas in a specified area” of the facility, which has been the site of a standoff with the militant group.

The army surrounded the facility as part of its ground offensive against Hamas. Israeli authorities claim the militants conceal military operations in the facility. But with hundreds of patients and medical personnel inside, Israeli authorities have refrained from entering.

In recent weeks, Israeli defense forces have “publicly warned time and again that Hamas’ continued military use of the Shifa Hospital jeopardizes its protected status under international law,” the military said.

“Yesterday, the IDF conveyed to the relevant authorities in Gaza once again that all military activities within the hospital must cease within 12 hours. Unfortunately, it did not.”

Hamas has denied the Israeli accusations that it uses the hospital for cover.

Military officials gave no further details but said they were taking steps to avoid harm to civilians.

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The operation unfolded after the military seized broader control of northern Gaza on Tuesday, including capturing the territory’s legislature building and its police headquarters, in gains that carried high symbolic value in the country’s quest to crush the ruling Hamas militant group.

Meanwhile, Israeli defense officials said they have agreed to allow fuel shipments into the Gaza Strip for humanitarian operations. It was the first time that Israel has allowed fuel into the besieged territory since the Hamas militant group’s bloody cross-border invasion on Oct. 7.

Inside some of the captured buildings, soldiers held up the Israeli flag and military flags in celebration. In a nationally televised news conference, Defense Minister Yoav Gallant said Hamas had “lost control” of northern Gaza and that Israel made significant gains in Gaza City.

But asked about the time frame for the war, Gallant said: “We’re talking about long months, not a day or two.”

One Israeli commander in Gaza, identified only as Lt. Col. Gilad, said in a video that his forces near Shifa Hospital had seized government buildings, schools and residential buildings where they found weapons and eliminated fighters.

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The army said it had captured the legislature, the Hamas police headquarters and a compound housing Hamas’ military intelligence headquarters. The buildings are powerful symbols, but their strategic value was unclear. Hamas fighters are believed to be positioned in underground bunkers.

For days, the Israeli army has encircled Shifa Hospital, the facility it says Hamas hides in, and beneath, to use civilians as shields for its main command base. Hospital staff and Hamas deny the claim.

Hundreds of patients, staff and displaced people were trapped inside, with supplies dwindling and no electricity to run incubators and other lifesaving equipment. After days without refrigeration, morgue staff on Tuesday dug a mass grave in the yard for more than 120 bodies, officials said.

Elsewhere, the Palestinian Red Crescent said Tuesday it had evacuated patients, doctors and displaced families from another Gaza City hospital, Al-Quds.

Israel has vowed to end Hamas rule in Gaza after the militants’ Oct. 7 attack into Israel in which they killed some 1,200 people and took roughly 240 hostages. The Israeli government has acknowledged it doesn’t know what it will do with the territory after Hamas’ defeat.

The onslaught — one of the most intense bombardments so far this century — has been disastrous for Gaza’s 2.3 million Palestinians.

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More than 11,200 people, two-thirds of them women and minors, have been killed in Gaza, according to the Palestinian Health Ministry in Ramallah. About 2,700 people have been reported missing. The ministry’s count does not differentiate between civilian and militant deaths.

Almost the entire population of Gaza has squeezed into the southern two-thirds of the tiny territory, where conditions have been deteriorating even as bombardment there continues. About 200,000 fled the north in recent days, the U.N. said Tuesday, though tens of thousands are believed to remain.

The U.N. agency for Palestinian refugees said Tuesday that its fuel storage facility in Gaza is empty and that it will soon end relief operations, including bringing limited supplies of food and medicine in from Egypt for more than 600,000 people sheltering in schools and other facilities in the south.

“Without fuel, the humanitarian operation in Gaza is coming to an end. Many more people will suffer and will likely die,” said Philippe Lazzarini, the commissioner-general of UNRWA. Israel has repeatedly rejected allowing fuel into Gaza, saying it will be diverted by Hamas for military use.

Plight of hospitals

Fighting has raged for days around Shifa Hospital, a complex several city blocks across at the center of Gaza City that has now “turned into a cemetery,” its director said in a statement.

The Health Ministry said 40 patients, including three babies, have died since Shifa’s emergency generator ran out of fuel Saturday. Another 36 babies are at risk of dying because there is no power for incubators, according to the ministry.

The Israeli military said it started an effort to transfer incubators to Shifa. But they would be useless without electricity, said Christian Lindmeier, a World Health Organization spokesman.

The Health Ministry has proposed evacuating the hospital with the supervision of the International Committee of the Red Cross and transferring the patients to hospitals in Egypt, but has not received any response, ministry spokesman Ashraf al-Qidra said.

While Israel says it is willing to allow staff and patients to evacuate, some Palestinians who have made it out say Israeli forces have fired at evacuees.

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Israel says its claims of a Hamas command center in and beneath Shifa are based on intelligence, but it has not provided visual evidence to support them. Denying the claims, the Gaza Health Ministry says it has invited international organizations to investigate the facility.

The evacuation at the Al-Quds Hospital followed “more than 10 days of siege, during which medical and humanitarian supplies were prevented from reaching the hospital,” Palestinian Red Crescent officials said.

In a post on X, they blamed the Israeli army for bombarding the hospital and firing at those inside.

The White House’s national security council spokesperson, John Kirby, said the U.S. has unspecified intelligence that Hamas and another Palestinian militants use Shifa and other hospitals and tunnels underneath them to support military operations and hold hostages.

The intelligence is based on multiple sources, and the U.S. independently collected the information, a U.S. official said on the condition of anonymity to discuss sensitive matters.

Kirby said the U.S. doesn’t support airstrikes on hospitals and does not want to see “a firefight in a hospital where innocent people” are trying to get care.

March for hostages

Hamas released a video late Monday showing one of the hostages, 19-year-old Noa Marciano, before and after she was killed in what Hamas said was an Israeli strike. The military later declared her a fallen soldier, without identifying a cause of death.

She is the first hostage confirmed to have died in captivity. Four were released by Hamas and a fifth was rescued by Israeli forces.

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Families and supporters of the around 240 people being held hostage by Hamas started a protest march from Tel Aviv to Jerusalem. The plight of the hostages has dominated public discourse since the Oct. 7 attack, with solidarity protests held across the country. The marchers, who expect to reach Jerusalem on Saturday, say the government must do more to bring home their loved-ones.

“Where are you?” Shelly Shem Tov, whose son, Omer, 21, is among the captives, called out to Netanyahu.

“We have no strength anymore. We have no strength. Bring back our children and our families home.”

Battle in Gaza City

Independent accounts of the fighting in Gaza City have been nearly impossible to gather, as communications to the north have largely collapsed.

Israeli military spokesman Daniel Hagari said Israeli forces have completed the takeover of Shati refugee camp, a densely built district bordering Gaza City’s center, and are moving about freely in the city as a whole.

Videos released by the Israeli military show troops moving through the city, firing into buildings. Bulldozers push down structures as tanks roll through streets surrounded by partially collapsed towers.

The videos portray a battle where troops are rooting out pockets of Hamas fighters and tearing down buildings they find them in, while gradually dismantling the group’s tunnel network.

Israel says it has killed several thousand fighters, including important mid-level commanders, while 46 of its own soldiers have been killed in Gaza. In recent days Hamas rocket fire into Israel — constant throughout the war — has waned, though two people were wounded Tuesday in a rocket attack on Tel Aviv. Details of the Israeli account and the extent of Hamas losses could not be independently confirmed.

—Jeffery and Keath reported from Cairo. Associated Press writers Amy Teibel in Jerusalem, Wafaa Shurafa in Deir al-Balah, Gaza Strip; and Samy Magdy in Cairo contributed to this report.