Hamas was set to release six more hostages from Gaza on Saturday in exchange for hundreds of Palestinian prisoners and detainees, after Israel confirmed that a body handed over hours earlier was that of hostage Shiri Bibas.

The fragile truce in the war between Israel and Hamas militants had been threatened with derailment by the misidentification of a body released on Thursday as that of Bibas, who was kidnapped with her two young sons and her husband in the Hamas attack on October 7, 2023.

However late on Friday, Hamas handed over another body, which her family said had been confirmed to be hers.

"Last night, our Shiri was returned home," the family said in a statement, which said she had been identified by Israel's Institute of Forensic Medicine.

In Gaza, armed and masked Hamas militants gathered at two sites in Rafah and Nuseirat where six living hostages were expected to be handed over to the Red Cross, which is to transport them to Israeli forces.

The are the last living hostages from a group of 33 due to be freed in the first stage of the ceasefire deal that took effect on January 19.

Four of the hostages, Eliya Cohen, 27, Tal Shoham, 40, Omer Shem Tov, 22, and Omer Wenkert, 23, were seized by Hamas gunmen during their attack on Israel on October 7, 2023.

Two others, Hisham Al-Sayed, 36, and Avera Mengistu, 39, have been held by Hamas since they entered Gaza separately under unexplained circumstances around a decade ago.

In return, Israel is expected to release 602 Palestinian prisoners and detainees held in its jails in the latest stage of an exchange that has largely held.

The Bibas family has been an emblem of the trauma suffered by Israel on that day. The misidentification of the remains of Shiri Bibas, as well as the staged handover of their coffins by Hamas outraged Israelis. Her husband Yarden, seized and helped separately from his family, was freed on February 1.

The Israeli military said intelligence assessments and forensic analysis of the bodies of 10-month-old Kfir Bibas and his four-year-old brother Ariel showed both had been killed deliberately by their captors.

Israel's Army Radio, citing the forensic conclusions, said Bibas was likely slain with her children. "Our Shiri was murdered in captivity and has now returned home to her sons, husband, sister, and all her family for rest," her family said in a statement.

Israeli Prime Minister Benjamin Netanyahu threatened to make Hamas "pay the full price" for failing to return the body but he refrained from walking away from the ceasefire agreement, which took effect on January 19.

Hamas, which has itself accused Israel of breaching the ceasefire by blocking vital aid supplies into Gaza, nonetheless formally informed Israel of the names of the hostages to be released on Saturday in a sign the handover would go ahead.

The ceasefire has brought a pause in the fighting, but prospects of a definitive end to the war remain unclear. Hamas, which killed some 1,200 people and took 251 hostages during its attack on Israel, has been at pains to demonstrate that it remains in control in Gaza despite heavy losses in the war.

The Israeli campaign killed at least 48,000 people, according to Palestinian health authorities, and reduced much of the enclave to rubble, leaving some hundreds of thousands in makeshift shelters and dependent on aid trucks.

Both sides have said they intend to start talks on a second stage, which mediators say aim to agree the return of around 60 remaining hostages, less than half of whom are believed to be alive, and the withdrawal of Israeli troops.

But hopes of a deal have been clouded by disagreements over the future of Gaza, that have been deepened by shock across the region over U.S. President Donald Trump's proposal to clear the enclave of Palestinians and develop it as a Riviera-style resort under U.S. control.