TEL AVIV - Israeli investigations into the killing of three hostages in the Gaza Strip and unintended strikes on buildings in the enclave are casting new light on Israel’s tactics in what is already one of the century’s most destructive wars, even as Israeli officials say there will be no letup in the assault.

In findings announced Thursday, the Israel Defense Forces said that the shooting deaths of three Israeli hostages by IDF soldiers this month as they attempted to identify themselves “could have been prevented” and that airstrikes this week are likely to have caused unintentional harm to civilians.

The probes address the main points of criticism of the Israeli campaign, both domestically - the government’s failure to protect and secure the release of the hostages remaining in the Gaza Strip - and internationally - the catastrophic civilian toll in the enclave.

Israeli forces have killed more than 21,500 people in Gaza and wounded more than 55,000 in the past three months, according to the Gaza Health Ministry. Israel launched the campaign after Hamas and allied fighters overran communities in southern Israel on Oct. 7, killing around 1,200 people and taking more than 200 hostage, according to Israeli authorities.

The Biden administration, while supportive of the Israeli campaign to eradicate the Islamist militant group Hamas, which controls Gaza, has pressured the government of Prime Minister Benjamin Netanyahu to do more to minimize civilian deaths in the enclave.

Israeli fighter jets on Dec. 24 attacked targets at the Maghazi refugee camp in central Gaza. At least 80 people were killed, the director of al-Aqsa Martyrs Hospital said.

The IDF said Thursday that it was targeting “Hamas operatives” but that an initial investigation had “revealed that additional buildings located near the targets were also hit … which likely caused unintended harm to additional uninvolved civilians.”

The IDF did not expand on why the strikes were so destructive, but a military official told the Israeli public broadcaster Kan that “the weaponry did not match the nature of the attack, so extensive collateral damage was caused.” In a U.S. intelligence assessment released this month, analysts found that almost half of the munitions Israel had used in Gaza were unguided bombs - which can miss a target by up to 100 feet.

Israel has rejected international calls for a cease-fire. “Whoever talks about stopping - there is no such thing,” Netanyahu told soldiers in northern Gaza this week. “We are not stopping. The war will continue until the end, until we finish it. No less.”

Family members of hostages who are still being held in the enclave worry that the Israeli campaign is putting their loved ones in greater danger. Hamas released 110 hostages last month in exchange for the Israeli release of Palestinians detained in the West Bank, but more than 100 hostages remain - or have been killed - in Gaza.

When the IDF troops killed the three Israel hostages this month, Lior Peri told The Washington Post, “we were terrified to see our greatest fear become a reality.” His 79-year-old father, Chaim, is still in Gaza.

The IDF said Thursday that the soldiers “carried out the right action to the best of their understanding of the event at that moment” but that the deaths “could have been prevented.”

Israeli troops raiding buildings in Gaza City on Dec. 10 heard calls in Hebrew asking for help, the IDF said. They assessed it to be a Hamas trap, a tactic that Israel says the group has used.

On Dec. 14, soldiers saw signs that read “SOS” and “save three kidnapped people.” The next day, an IDF soldier saw three people - all shirtless, one of them waving a white flag - and opened fire, killing two. Commanders ordered a stop to the shooting. The third person reemerged, and one soldier shot and killed him. The IDF said the soldier didn’t hear the order to stop.

“It should not have happened,” Tal Heinrich, a spokeswoman for the prime minister’s office, said Friday. “We learned difficult lessons, and our forces are implementing the lessons that we learned.”

Miri Eisin, director of the International Institute for Counterterrorism at Reichman University, said the investigations are evidence that the IDF is holding itself accountable. “You need to make sure soldiers understand the depth of the actions that they take,” said Eisin, a colonel in the IDF reserves. “When you go beyond what you’re allowed to do, you need to call yourself out.”

The killings of the three hostages outraged Israelis. Thousands rallied in Tel Aviv to call on Netanyahu to do more to bring the other hostages home. Hamas has said it will release more hostages only when the fighting ends.

“There will be no prisoner swap deal nor negotiations under fire until the Israeli aggression ends,” Bassem Naim, a member of the Hamas political bureau in Doha, Qatar, said in a video statement. “Meanwhile, we can say we are open to any initiative that can end this Israeli genocidal war.”

A strike near Kuwaiti Hospital in Rafah on Thursday killed at least 18 people and wounded dozens, the hospital’s director said. An estimated 100,000 Gazans, displaced by fighting in the north, have crowded into the southern city. They are struggling with shortages of water, food and shelter; insufficient aid; and continuing bombardment.

“I escaped death, only to find the situation here equally perilous,” said Ihab Al-Daya, who fled central Gaza to shelter in Rafah.

“There is no water, no food, and nowhere to sleep,” he said. “Shells are constantly being fired at us.”

The plight of Gazan civilians, pushed by the military campaign into shrinking spaces within the already cramped enclave, has stirred protests around the world. But the Israeli government faces little pressure domestically to ease up. Israeli disapproval of the government is high, but so is support for the war.

Still, some Israelis are calling for an end to hostilities. Hundreds rallied in Tel Aviv on Thursday evening to demand a cease-fire.

“I came to protest two main things,” Oren Ben Natan said. “Firstly, how our government abandoned 108 hostages who are still held by Hamas. And second, the massacre in Gaza.”

The 24-year-old held a sign that read “There is no security without a political solution.”

“Beyond it being a horrifying war crime,” Ben Natan said, “it is 100 percent clear to me that this will not lead us to peace and quiet, but onto the next round, which will be deadlier, to both Israelis and Palestinians alike.”

Across the street, onlookers shouted curses at the demonstrators.

Hazem Balousha in Amman, Jordan, and Paul Schemm in London contributed to this report.