At the core of the ceasefire deal between Israel and Hamas that ends hostilities in Gaza for at least six weeks is the release of some of the remaining Israeli hostages held by the militant group.
According to Israeli tallies, about 251 people were taken hostage and 1,200 killed by Hamas in the October 7, 2023, terror attacks, when the group controlling Gaza launched a surprise assault on military bases, towns and a music festival in southern Israel.
Since then, at least 46,788 Palestinians have been killed by Israel's invasion of the blockaded Gaza Strip, according to Palestinian health authorities, with thousands more feared dead under the ruins of buildings destroyed in air strikes and from starvation and disease.
The first stage of the ceasefire deal, approved by Israel's cabinet, includes a six-week halt to fighting and negotiating an end to the 15-month war.
A list of 33 hostages — out of 100 estimated still in Gaza — to be released largely includes children, elderly people and women, though it is unknown how many are still alive after 15 months in captivity.
From this list, three women will be the first to be released.
Hundreds of Palestinians held prisoner by Israel will be released as part of the hostage exchange, including all women and children under 19 held since October 7.
The Bibas family
Known for being the youngest hostage taken into Gaza, one-year-old Kfir Bibas is listed for release alongside his five-year-old brother Ariel and mother Shiri.
Hamas said in November 2023 the trio had been killed in an Israeli strike, but there has been no official confirmation of their deaths.
The two children were taken along with their parents from Kibbutz Nir Oz in southern Israel on October 7, and have become associated with the colour orange in Israel because of their red hair.
Their father and Shiri's husband, Yarden Bibas, is also on the list of hostages to be released, but he is believed to have been held separately from his family.
It is unknown if Mr Bibas is alive or dead.
Shlomo Mansur
Shlomo Mansur is the oldest hostage in Gaza at 86, an Iraqi Jew born in Baghdad who immigrated to Israel in the 40s.
According to the Hostages and Missing Families Forum, Mr Mansur is a carpenter, husband and grandfather to 15.
He was abducted from Kibbutz Kissumfim on October 7.
In an interview with the Jerusalem Centre for Security and Foreign Affairs, Mr Mansur's sister, Hadassah Laazar, said she was hopeful she would see him again after no sign of him was found following the attack on his kibbutz.
"I don't know if he's still alive," she said, having received no information since he was taken.
Nova festival hostages
One of the multiple civilian sites targeted in the October 7 attacks was the Nova music festival in Re'im, southern Israel, attended by about 3,000 people.
According to Israeli tallies, about 364 people were killed during the early morning attack on the festival, and dozens were taken hostage, including:
Guy Gilboa-Dalal: A programming and Japanese student, the 23-year-old went to the music festival with his best friend Evyatar David, who is also believed to be held hostage by Hamas.
Romi Gonen: The 24-year-old dancer's family has held regular dance classes in Tel Aviv to honour the hostage, and her family, including her sister Yarden Gonen, has appeared on Israeli and US media regularly to advocate for her release.
"It's a crucial time to do everything we can to save my little sister and the other 100 hostages," Ms Gonen told Fox News in December.
Neither of the two have been confirmed alive nor dead by the Israeli government.
Hostage for a decade
Two of the hostages listed for release were not taken on October 7, but instead have been held captive for roughly a decade in Gaza.
Both Israeli citizens, 36-year-old Bedouin Arab Hisham al-Sayed and 38-year-old Avera Mangistu crossed into Gaza on foot in 2015 and 2014 respectively, and have been held by Hamas ever since.
A 2017 Human Rights Watch (HRW) report said both men had histories of serious mental health conditions and were known to wander far on foot.
The report said Hamas had designated them as soldiers, but the HRW investigation found they were not combatants or affiliated with the Israeli government in any way.
Mr al-Sayed appeared in a 2022 video released by Hamas that showed him lying in a hospital bed breathing into an oxygen mask without speaking.
'Unique situation' for survivors
For those hostages still alive after 15 months of captivity, reintegrating into society would be tremendously difficult, Israeli psychologist Vered Atzmon Meshulam told the ABC.
"We've never been in a situation where we're receiving back hostages after [such a] long time," Ms Meshulam said.
"We are learning to deal with this complicated trauma that we know they are going through," she said.
"First we will need to help them get back their dignity, their secure feeling about life … and being safe.
"It's a very important part of being alive."
ABC/AFP/AP
