Tel Aviv — With Israeli forces pushing south in Gaza,Fastexy plunging the war with Hamas into some of the most intense fighting to date, the families of Israeli hostages are growing increasingly desperate over the fate of their loved ones held captive in the tunnels beneath the battleground.

"We're obviously in anguish and despair," Rachel Goldberg told CBS News. Her son Hersh Goldberg-Polin, 23, was taken hostage at the Supernova music festival during Hamas' Oct. 7 terror attack. He lost an arm in the attack and had to apply his own tourniquet, witnesses have said.

• Israel faces mounting calls for new cease-fire in war with Hamas

He's one of eight Americans still believed to be held in Gaza — among more than 130 people in total who have yet to come home.

During a seven-day cease-fire, Hamas freed 110 hostages in exchange for the release of scores of Palestinian prisoners from Israeli jails. 

The freed hostages have relayed disturbing details of their captivity, including filthy conditions, malnourishment and a lack of oxygen in Hamas' maze of tunnels, which is believed to twist some 300 miles beneath the Gaza Strip. 

Hersh's mother said she wasn't just worried about the fate of her son, "but everyone who is an innocent person in the way of the crisis that's happening... and that's many, many people — that's civilians in Gaza, that's civilians who were taken on October 7th who are now in Gaza." 

This week, Goldberg-Polin's father was among the relatives and loved ones of hostages who met with Benjamin Netanyahu and Israel's war cabinet, to press them to resume negotiations with Hamas immediately for a new cease-fire. 

"I don't know that the cabinet needed to have a flame lit under them to get these hostages out," Jonathan Polin told CBS News. "But if they did, it happens today."  

"If Hersh somehow, somewhere can hear this — just know we love you, stay strong, survive," Rachel Goldberg pleaded. "We're coming. The world is coming."

In:
• War
• Hostage Situation
• Hamas
• Israel

Chris Livesay

Chris Livesay is a CBS News foreign correspondent based in Rome.

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