The Israel Defense Forces on Sunday announced that Sgt. Shay Levinson, who until now had been identified as a hostage, was killed in battle on Oct. 7 and his body is being held in the Gaza Strip.

Israeli officials say 532 IDF soldiers have been killed, including 195 since the ground operations in Gaza began.

-ABC News' Anna Burd

ABC News' Matt Gutman got a close-up look at a vast Hamas tunnel complex where hostages were reportedly held captive.

Israeli Prime Minister Benjamin Netanyahu said Israel will "continue the war on all fronts and in all sectors."

"We do not give immunity to any terrorist -- not in Gaza, not in Lebanon, not in Syria and not anywhere," Netanyahu said in the statement Sunday, written in Hebrew.

The prime minster added, "Whoever tries to hurt us -- we hurt him."

Netanyahu said he's working to secure the return of all the hostages "around the clock," and added: "But to be clear: I reject outright the terms of surrender of the monsters of Hamas."

Netanyahu also said he had a conversation with President Joe Biden over the weekend, in which he emphasized "determination to complete all war objectives, and to ensure that Gaza will no longer pose a threat to Israel," according to the prime minister's statement.

"That is why I insist that after we achieve complete victory, after we eliminate Hamas -- there will be no factor in Gaza that finances terrorism, educator of terrorism or courier of terrorism," Netanyahu said.

"Gaza must be demilitarized, under full security control of the State of Israel," he said. "I will not compromise on full Israeli security control over all the territory west of Jordan."

Netanyahu added he will continue to "firmly" stand by his insistence to prevent the establishment of a Palestinian state for as long as he is prime minister.

-ABC News' Jordana Miller

More than 25,000 people have been killed in the Gaza Strip since the beginning of the Israel-Hamas war, the Gaza Ministry of Health said Sunday.

At least 62,681 people have been injured since the war began, said the ministry, which operates under the Hamas Authority.

A ministry spokesperson said at least 178 bodies were brought to hospitals in the last day.

-ABC News’ Nasser Atta and Edward Szekeres