Israel has accused Hamas of violating the ceasefire deal after forensic testing revealed the body returned from Gaza on Thursday was not that of Shiri Bibas.
The three other bodies handed over have been identified as her sons, Ariel and Kfir, who would have been aged five and two, and Oded Lifshitz, the Israel Defense Forces (IDF) said.
Hamas has not yet commented on Israel’s claim.
Israel demanded the return of her body along with the other remaining hostages.
Prime Minister Benjamin Netanyahu said in a statement on Friday that Israel would “ensure that Hamas pays the full price for this cruel and evil violation of the agreement”.
“We will act with determination to bring Shiri home along with all our hostages – both living and dead,” Netanyahu said.
The IDF posted on X that “during the identification process, it was determined that the additional body received is not that of Shiri Bibas, and no match was found for any other hostage. This is an anonymous, unidentified body.”
“This is a violation of utmost severity by the Hamas terrorist organisation, which is obligated under the agreement to return four deceased hostages. We demand that Hamas return Shiri home along with all our hostages.”
The IDF said that the two children “were brutally murdered by terrorists in captivity in November 2023”, according to intelligence and forensic findings. Hamas had said the boys and their mother were killed in an Israeli bombing.
The Hostages and Missing Families Forum said it was “horrified and devastated by the news that their mother, Shiri, was not returned—despite the agreement and our desperate hopes”.
Shiri, Ariel and Kfir Bibas were aged 32, four and nine months when they were kidnapped during the Hamas attacks on Israel on 7 October 2023. They have become a symbol for many in Israel and news of their deaths was met with an outpouring of grief.
The children’s father Yarden Bibas, 34, was released by Hamas on 1 February.
Israel has confirmed that the fourth body returned on Thursday was that of veteran peace activist, Oded Lifshitz.
The release of hostages’ bodies was agreed as part of the ceasefire deal which came into effect on 19 January, and Israel has confirmed it expects eight bodies will be handed over.
The two sides agreed to exchange 33 hostages for about 1,900 prisoners by the end of the first six weeks of the ceasefire.
Talks on progressing to the next phase of the deal – under which the remaining living hostages would be released and the war would end permanently – were due to start earlier this month but have not yet begun.
Twenty-eight hostages and more than 1,000 prisoners have so far been exchanged.
Sixty-six hostages taken on 7 October are still being held in Gaza. Three other hostages, taken more than a decade ago, are also being held. About half of all the hostages still in Gaza are believed to be alive.
About 1,200 people – mostly civilians – were killed in the Hamas attacks on 7 October 2023 and 251 others taken back to Gaza as hostages. Israel launched a massive military campaign against Hamas in response, which has killed at least 48,297 Palestinians – mainly civilians – according to the Hamas-run health ministry.
Also on Thursday, three buses exploded in Bat Yam, south of Tel Aviv, in what Israeli police said is a suspected terror attack.
Devices in two other buses failed to explode, they said, adding that “large police forces are at the scenes, searching for suspects”. No casualties have been reported.
In response, Prime Minister Benjamin Netanyahu’s office announced he had ordered the IDF to carry out an “intensive operation against centers of terrorism” in the West Bank.