Israel has recovered the bodies of six hostages held by Hamas in Gaza, including a young Israeli-American man whose parents had met with world leaders.
All six were killed shortly before they were to be rescued by Israeli forces, AP reported on Sunday.
They have been named as Eden Yerushalmi, Carmel Gat, Alexander Lobanov, Almog Sarusi, Ori Danino, and 23-year-old Hersh Goldberg-Polin - the Israeli-American man.
Five of the hostages were seized at a music festival in southern Israel during Hamas' attack last October which triggered the war. The sixth hostage, Carmel Gat, was abducted from the nearby farming community of Be'eri.
Their recovery sparked calls for mass protests against prime minister Benjamin Netanyahu, who many families of hostages and much of the wider Israeli public blame for failing to bring them back alive in a deal with Hamas to end the 10-month-old war. Negotiations over such a deal have dragged on for months.
In a separate development, gunmen killed three people when they opened fire on a vehicle in the occupied West Bank, where Israel has been carrying out large-scale military raids in recent days.
"According to preliminary information, they were cruelly murdered by Hamas terrorists shortly before we reached them," Daniel Hagari, the Israeli military spokesperson, said.
There was no immediate comment from Hamas. The militant group has offered to release the hostages in return for an end to the war, the withdrawal of Israeli forces and the release of a large number of Palestinian prisoners, including high-profile militants.
Netanyahu has vowed to continue the war until Hamas is destroyed and says military pressure is needed to bring home the hostages.
Israel's Channel 12 reported that he got into a shouting match last week with his defence minister, Yoav Gallant, who accused him of prioritising control over a strategic corridor along the Gaza-Egypt border — a major sticking point in the talks — over the lives of the hostages.
Israel's mostly ceremonial president, Isaac Herzog, said: "The heart of an entire nation is shattered to pieces."
Mr Gallant said: "In the name of the state of Israel, I hold their families close to my heart and ask forgiveness."
There was no immediate comment from Netanyahu.
A forum of hostage families called for a massive protest on Sunday, demanding a "complete halt of the country" to push for the implementation of a cease-fire and hostage release.
US president Joe Biden, who had met with the parents, said he was "devastated and outraged."
"It is as tragic as it is reprehensible," he said.
"Make no mistake, Hamas leaders will pay for these crimes. And we will keep working around the clock for a deal to secure the release of the remaining hostages."
Vice president Kamala Harris also released a statement, saying her prayers were with the Goldberg-Polin family and condemning Hamas.
