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Hersh Goldberg-Polin, an American-Israeli held hostage by Hamas in Gaza, has died, his family said on Sunday, dealing fresh heartbreak to the families of captives who fear time is running out for their loved ones seized by the militants more than 10 months ago.
The announcement came hours after the Israeli military said it had found the bodies of six hostages held in Gaza.
The 23-year-old's parents have been among the most vocal of the hostage families pushing Israeli Prime Minister Benjamin Netanyahu to seek a deal securing their relatives' return, and they gave an emotional address at this month's Democratic National Convention.
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His ordeal, after he was taken at gunpoint by Hamas militants at the Nova music festival on October 7, resulted in him becoming one of the faces of the devastating hostage crisis that has challenged Netanyahu's leadership and triggered widespread destruction in Gaza.
"With broken hearts, the Goldberg-Polin family is devastated to announce the death of their beloved son and brother, Hersh. The family thanks you all for your love and support and asks for privacy at this time," the family said in a statement.
CNN has reached out to the family.
The identities of the other five people have not yet been released.
US President Joe Biden said the six bodies were recovered from a tunnel under the city of Rafah in southern Gaza.
"I am devastated and outraged," Biden said in a statement released by the White House that also paid tribute to Goldberg-Polin's parents.
"They have been courageous, wise, and steadfast, even as they have endured the unimaginable," Biden said.
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"They have been relentless and irrepressible champions of their son and of all the hostages held in unconscionable conditions."
Goldberg-Polin and friends hid inside a small bomb shelter when Hamas gunmen began their kidnap and murder rampage.
As militants began to lob grenades into the bunker, he rushed to throw them out, before his arm was blown off from the elbow down, according to a firsthand account from his friend.
News of more hostage deaths piles pressure Netanyahu as anger inside Israel swells over the failure to strike a ceasefire deal, and as stark disagreements between the prime minister and his military leaders increasingly spill out into the open.
It also ups the stakes for Biden to push US ally Israel to find a way out of a devastating war in Gaza that has inflamed global public opinion and repeatedly threatened to spiral into an all-out regional conflict.
"Make no mistake, Hamas leaders will pay for these crimes. And we will keep working around the clock for a deal to secure the release of the remaining hostages," Biden said in his statement on Goldberg-Polin's death.
Israel launched its war against Hamas in Gaza after the militant group's cross-border October 7 attacks, in which more than 1,200 Israelis were killed and 250 taken hostage, according to Israeli authorities.
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More than 40,000 Palestinians have been killed in Gaza since the war began, according to the health ministry in the enclave.
Anger has been growing inside Israel, led by many hostage families, who believe Netanyahu and key far-right cabinet colleagues have been stalling on achieving a ceasefire resolution with Hamas that might bring those captured and killed home.
Netanyahu has been adamant that a deal can only be signed when Israel's safety is assured.
But domestic pressure is building.
A group representing the hostage families called for the public to mobilize after the Israel Defense Forces (IDF) earlier reported finding "a number of bodies" in Gaza.
The demands by the Hostages and Missing Families Forum came as thousands rallied across Israel on Saturday demanding a ceasefire-for-hostages deal.
"Netanyahu abandoned the hostages! This is now a fact," a statement issued by the families' forum read.
"Starting tomorrow the country will tremble. We call on the public to prepare. We will stop the country."
The forum said it will release more details about what it is calling for on Sunday.
'Anguish and misery'
The death of Goldberg-Polin in particular will reverberate not just in Israel but in US political circles.
His parents Rachel and Jonathan have regularly met top US officials in Washington to press the case of the hostages and their emotional address to top Democrats at the convention in Chicago inextricably tied the hostages' fate to US policy over the war in Gaza.
Rachel Goldberg-Polin told CNN in January that she wears a piece of tape marking each day that has passed since her son was kidnapped.
At her convention speech, she described life since October 7 like living on "another planet."
"Anyone who is a parent or has had a parent can try to imagine the anguish and misery that John and I and all the hostage families are enduring," she told delegates.
Biden said on Saturday evening that his staff has been in touch with Israeli officials about the unfolding situation but noted that the bodies had not yet been identified.
Biden also called for an end to the war, expressing optimism that an agreement could be reached on a ceasefire-for-hostages deal and adding that parties involved in the negotiation have said they "agree on the principles."
"It's time this war ended," Biden added. "I think we're on the verge of having an agreement. It's time to end it. It's time to finish it."
The US, Qatar and Egypt, who have acted as mediators, this month renewed a push to reach a hostage and ceasefire deal between Israel and Hamas.
The mediators have proposed a three-phase approach: a first phase involving a six-week ceasefire; a second phase that would release all hostages and a withdrawal of all IDF presence from Gaza; and a third reconstruction phase.
However, the current proposal, if agreed upon, essentially allows Israel and Hamas to abandon discussions after the first phase, and Israel has made it clear that a break in the fighting may be just that and it is not ready to agree to a permanent ceasefire.
More than 100 hostages taken from Israel were freed under a temporary truce last year and eight have been rescued alive – including Farhan Al-Qadi, who was recovered from a Hamas tunnel this week.
However, more than 100 are thought to remain in Gaza.
CNN previously reported that there are 107 total hostages, living and dead, being held in Gaza, according to Israel's Prime Minister's Office and the Hostages and Missing Families Forum.
Of that number, 103 hostages are from the October 7 Hamas attack on Israel.
Of those, 33 are presumed dead, according to the forum, in figures given before Sunday's announcement.
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