Israel says the next release of captives will take place on Thursday, followed by another on Saturday.
Israel says the list of Hamas shows that eight of the 33 slaves are freed in the first part of Gaza ceasefire agreement they are dying.
Government spokesman David Mencer told reporters on Monday that Hamas said 25 others were still alive. Israel overnight said it had received a list of hostages from Hamas.
“Families have been informed of the condition of their relatives,” Mencer said, without giving the names of the deceased.
Israel said the next release of prisoners would take place on Thursday, followed by another on Saturday.
About 90 slaves are still being held. Before that, Israel believed that about 35 of them had died.
The peace agreement in the Israeli-Hamas conflict, which was announced earlier in January after months of fruitless negotiations, came into effect on January 19, ending more than 15 months of devastating war in Gaza that began with violence led by Hamas on October 7, 2023. .
Under the first phase of the agreement, 33 prisoners in Gaza will be freed in exchange for more than 1,900 Palestinians held in Israeli custody.
Seven women of Israel they have been released since the start of the deal, as have 290 Palestinian prisoners.
Two Israeli women, Arbel Yehud and Agam Berger, were released on Thursday along with an unidentified third, following negotiations between Hamas and Israel.
Their impending release was announced by Prime Minister Benjamin Netanyahu on Sunday night as part of a peace deal with Hamas.
According to Israel, Arbel Yehud, as a woman and a civilian, was supposed to be released last Saturday in the second exchange of prisoners in the ceasefire agreement.
When he did not appear, the Israeli government accused Hamas of violating the agreement and in retaliation prevented Palestinian refugees from returning to northern Gaza.
Hamas accused Israel of violating the ceasefire and said it had informed mediators that Yehud was alive and had offered guarantees for his release.
On Monday, following Hamas' promise to release Yehud and other prisoners this week, the blockade was lifted.
Therefore, hundreds of thousands of Palestinians displaced from Gaza began a journey back to the destroyed homes in the northern Gaza Strip later on Monday for the first time since the devastating war began.
The United Nations said more than 200,000 people were seen moving north into Gaza on Monday morning alone.
According to UN data, nearly two-thirds of all homes in Gaza were destroyed or severely damaged during the conflict, and nearly 90 percent of Gaza's 2.1 million people fled their homes.
The Ministry of Health in Hamas-run Gaza said on Monday that the death toll from Israel's war in Gaza has reached 47,317, with the number rising despite the absence of an end to the war as new bodies are found under the rubble.
The ministry said hospitals in the Gaza Strip had received 11 bodies in the past 24 hours – nine recovered from the violence, and two new deaths. It did not explain how the new deaths occurred.
The ministry said the Israeli attack also injured at least 111,494 people.
At least 1,139 people were killed in Israel during the terrorist attack led by Hamas on October 7, 2023 and more than 200 were taken into captivity.