An Israeli soldier who the military feared had been abducted by Hamas gunmen in a firefight Friday that shattered a temporary cease-fire in Gaza was declared dead Sunday, just hours after Prime Minister Benjamin Netanyahu signaled that military operations against Palestinian militants would continue.

“We will take as much time as necessary, and will exert as much force as needed,” Netanyahu said Saturday. He said that Hamas will pay “an intolerable price” for its attacks.

Earlier, Israeli officials had said they would not send representatives to negotiations planned for Sunday in Cairo, and reports circulated in the Israeli news media that Netanyahu was preparing to pull his country’s ground forces from Gaza.

The Israeli prime minister defied those expectations but left the door open to a possible de-escalation, saying that forces could be redeployed once the military completes its mission to destroy all Hamas tunnels between Gaza and Israel.

The announcement suggested that Israel plans to finish its latest Gaza campaign on its own terms, without negotiating a deal with Hamas — much in the way Israel’s Operation Cast Lead ended in the winter of 2008-2009.

Early on Sunday, the Israeli military announced that 2nd Lt. Hadar­ Goldin, 23, of the Givati infantry brigade, had been killed during fighting Friday. Israel’s defense minister, along with the chief military rabbi, met with the soldier’s family at their home in the town of Kfar Saba.

Hundreds of people from around the country also gathered outside their home, praying and showing their support. There was an outpouring of grief when the military’s announcement was made public.

The reported abduction of Goldin on Friday brought to an end after just 90 minutes a promised 72-hour cease-fire, as Israel responded to what it said was a clear violation of the terms of the truce.

Goldin’s unit, which was preparing to destroy a tunnel between Gaza and Israel, was ambushed by Palestinian militants, including a suicide bomber. Two Israeli soldiers were killed, and Goldin was thought to have been pushed back through the tunnel. But the Israeli military’s announcement said the finding that Goldin had died was based on evidence recovered from the scene of the attack that suggested he had not survived the ambush.

Hamas insists the incident occurred before the cease-fire took hold and that it was Israel that broke the terms of the truce.

The last major battle between Israel and Hamas, in 2012, resulted in an Egyptian-mediated cease-fire. But this round has proved immune to diplomacy, with multiple efforts to stop the bloodshed collapsing in their first minutes or hours. The result is that this conflict has gone on far longer, and the death toll has been significantly higher, than in either of the previous two bouts.

An intense bombardment of Gaza on Saturday, concentrated in the area where Goldin was thought to have been abducted, left at least 112 Palestinians dead, according to officials with the Gaza Health Ministry. The deaths raised the Palestinian toll over nearly a month of fighting to more than 1,700.

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By rejecting further talks, “Israel is telling Hamas that they’re not going to get anything,” said Amos Yadlin, a former head of Israel’s military intelligence division. Hamas “will tell themselves a victory story. But this horrible situation in Gaza will be on their hands.”

Hamas, the Islamist movement that controls Gaza and that is considered a terrorist organization by the United States, has repeatedly demanded an end to the blockade of Gaza by land, air and sea that has effectively cut the territory off from the outside world.

The movement showed no sign of a flagging will to fight Saturday, firing dozens of rockets toward Israel, and causing a half-dozen injuries. Three civilians have been killed by mortar rounds or rockets fired by militants from Gaza into Israel.

Hamas spokesman Fawzi Barhoum said in a statement that the group would continue to battle, and that Netanyahu’s announcement “was an attempt to fake an illusion of victory for his government.”

The count of Israeli soldiers killed in Gaza operations rose to 64 early Sunday after Israel declared that Goldin was dead.

In a statement early Saturday morning, Hamas’s military wing said it had no knowledge of Goldin’s whereabouts and suggested that he might have been killed by the Israeli airstrikes that followed the apparent abduction.

“We have lost contact with the group of fighters that took part in the ambush and we believe they were all killed in the [Israeli] bombardment,” the statement said. “Assuming that they managed to seize the soldier during combat, we assess that he was also killed in the incident.”

Before announcing Goldin’s death, Israeli officials had said that troops were conducting extensive operations to try to find the missing soldier. As reports circulated in the Israeli media Saturday evening that Netanyahu was prepared to withdraw ground troops from Gaza, Goldin’s parents told reporters that the military should not pull out until their son is found.

“He was sent there to protect Israel. I demand from the state of Israel that it not leave Gaza until it brings my son home,” said Goldin’s mother, Hedva.

The scuttled Friday morning cease-fire was just the latest in a series of attempts to end the fight through a negotiated truce. But those efforts may have hit a permanent impasse.

In a sign of how little hope exists for a diplomatic breakthrough to end the conflict, Israel said Saturday that it would not attend negotiations that had been planned for Sunday in Cairo as part of the original cease-fire deal. Foreign Ministry spokesman Paul Hirschson said Israel was open to a new framework for talks but would not seek one out.

“When there’s a credible proposal, we’ll listen,” he said. “But there’s a certain skepticism about whether these guys have any interest in a cease-fire.”

Hamas spokesman Sami Abu Zuhri said Palestinian factions, including Hamas, would attend the talks but that delegates from Gaza would not be among them because of security concerns.

Despite Israel’s absence, Egyptian President Abdel Fatah al-Sissi suggested the talks would go forward, saying that Egypt’s proposal represented “the real chance to find a solution to the crisis in Gaza and to end the bloodshed.”

There was little indication on the ground in Gaza on Saturday that a resolution to the conflict was near. Palestinian officials said that several mosques and the Islamic University in Gaza City were among the targets of overnight airstrikes. Israel said the buildings were being used to develop and store weapons.

But in a small sign that Israel may be reaching the end of its target list, residents of the town of Beit Lahiya, in the northern Gaza Strip, were told Saturday afternoon that they could return to their homes because Israel’s operations in those areas had ceased.

Netanyahu faces pressure from right-wing members of his cabinet to widen the scope of the operation and try to eliminate Hamas entirely from Gaza. But with Israeli casualties mounting, such a choice comes with substantial peril, and indications were growing Saturday that Israel would stop well short of that mark.

“If the Israelis push further into Gaza, it will be a big mess,” said Hamza Abu Shanab, a political analyst whose father was a top Hamas leader in Gaza before Israel assassinated him in 2003. “More Israelis will be killed. More Israelis will be kidnapped. Hamas will fight back severely.”

Raghavan reported from Gaza City. Ruth Eglash in Jerusalem and Islam Abdel Karim in Gaza City contributed to this report.