Updated December 16, 2023 at 12:27 PM ET

TEL AVIV, Israel — An investigation into the killing of three hostages held by Hamas in Gaza has found that the captives were shirtless and waving a white flag as Israeli soldiers fired on them.

The preliminary report Saturday by the Israel Defense Forces, or IDF, said the hostages had managed to evade their captors in the northern Gaza neighborhood of Shijaiyah before they were "mistakenly identified" as they exited a building on Friday. They were then shot by an Israeli soldier.

Two were killed immediately and another was wounded and ran back into the building, an Israeli official said in a briefing on Saturday. Soldiers then heard a cry for help in Hebrew. The soldier's battalion commander ordered the firing to stop. The third hostage later died of his wounds.

Last month, Hamas released more than 100 hostages in a seven-day truce in exchange for about 300 Palestinian prisoners and detainees held by Israel. The three captives killed on Friday were among the more than 100 hostages believed still held by the Palestinian militant group.

The preliminary report concluded that the soldiers involved in the accidental shooting did not follow the IDF's own rules of engagement. The hostages had been dressed in civilian clothes and waving a white flag before they were shot by a soldier who felt under threat, the military official said.

Hamas militants wear civilian clothes to deceive the military, the official said.

Israeli Prime Minister Benjamin Netanyahu called the deaths of the three captives — Yotam Haim, Samer Fuad El-Talalka and Alon Shamriz, all in their 20s — an "unbearable tragedy."

Families of the hostages have kept up public pressure on Netanyahu's government, calling for Israel's first priority to be their safe return, and not the military operation to eradicate Hamas. Adding to that pressure in recent weeks, captives who were released during last month's cease-fire have been speaking publicly about their time in captivity.

The scene at "hostages square" in Tel Aviv

On Saturday afternoon at "hostages square" in central Tel Aviv, people gathered to hear from families of the captives. Ruby Chen, the father of hostage Itay Chen, 19, said he met last week with President Biden, U.S. Secretary of State Antony Blinken and other senior U.S. officials.

"We wanted to give them the gratitude of all the Jewish people [for] all they've done for us," Chen said. "I don't think there was any other president who was so willing to do anything possible, 24/7, on behalf of his administration to help us see our loved ones."

But he criticized Netanyahu's government, who he said was not interested in meeting with families of the hostages. "The Israeli government needs to be active," Chen said. "They need to put an offer on the table, including prisoners with blood on their hands," he said, referring to the release of Palestinians held in Israeli jails, "... to get the hostages back alive."

Hadas Pilowsky-Ron echoed that sentiment, saying releasing the hostages "must be the most important goal of the war."

"There is no choice ... bring the hostages [home] first," she said. The Israeli military can always go back and get Hamas later, but "every day that goes by, another hostage dies and this is the most important issue now."

Earlier, on Friday evening after the news of the accidental shootings broke, a group of people gathered in central Tel Aviv and marched through the city's streets at night, calling out to others to wake up and join them.

Among them was Adam Yekutieli, 37, an artist, who said the deaths of the three hostages reinforced for him that Israel needs to negotiate another cease-fire to free more of the captives.

"There's no military solution to this situation," he said. "Israel is bombing its way into a corner that it won't be able to get out of."

An Al Jazeera cameraman is killed in Gaza

Meanwhile, on Friday, veteran Al Jazeera cameraman Samer Abu Daqqa was killed in Gaza by fire from an Israeli drone at a school in the city of Khan Younis, the Foreign Press Association said.

The FPA said Daqqa's colleague, Wael Al-Dahdouh, was wounded in the incident.

"We consider this a grave blow to the already limited freedom of the press in Gaza and call on the army for a prompt investigation and explanation," the FPA said.

Israel's military said in a statement that it "takes all operationally feasible measures to protect both civilians and journalists."

"The IDF has never, and will never, deliberately target journalists," it said, adding that "Given the ongoing exchanges of fire, remaining in an active combat zone has inherent risks."

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