The mass outpouring on Sunday appeared to be the largest such demonstration in 11 months of war and protesters said it felt like a possible turning point, although the country is deeply divided.
Israel's largest trade union, the Histadrut, further pressured the government by calling a general strike for Monday, the first since the October 7 Hamas attack that started the war.
It aims to shut down or disrupt major sectors of the economy, including banking, health care and the country's main airport.
Many Israelis blame the government for failing to reach a deal to release the hostages. (AP PHOTO)
Cease-fire negotiations have dragged on for months. Many blame Netanyahu for failing to reach a deal, which opinion polls show a majority of Israelis favour.
But the prime minister also has significant support for his strategy of "total victory" against Hamas, even if a deal for the hostages has to wait.
Thousands of people, some of them weeping, gathered on Sunday night outside Netanyahu's office in Jerusalem. In Tel Aviv, hostages' relatives marched with coffins to symbolise the toll.
Three of the six hostages found dead — including an Israeli-American — were reportedly scheduled to be released in the first phase of a cease-fire proposal discussed in July. This fuelled fury and frustration among the protesters.
Grief turned into anger on the streets. (AP PHOTO)
"Nothing is worse than knowing that they could have been saved," said Dana Loutaly.
The military said all six hostages were killed shortly before Israeli forces arrived. "Whoever murders hostages doesn't want a deal," Netanyahu said, blaming the Hamas for the stalled negotiations.
One hostage was Israeli-American Hersh Goldberg-Polin, 23, who lost part of his left arm to a grenade in the attack. In April, Hamas issued a video that showed him alive.
The army identified the others as Ori Danino, 25; Eden Yerushalmi, 24; Almog Sarusi, 27; Alexander Lobanov, 33; and Carmel Gat, 40.
Three of the six hostages were due to be released in the first phase of a cease-fire proposal. (AP PHOTO)
The Israeli Health Ministry said autopsies had determined the hostages were shot at close range and died on Thursday or Friday.
The army said the bodies were recovered from a tunnel in the southern Gaza city of Rafah.
Lieutenant Colonel Nadav Shoshani, a military spokesperson, said Israeli forces found the bodies several dozen metres underground and there was no doubt Hamas had killed them.
Hamas has offered to release the hostages in return for an end to the war, the withdrawal of Israeli forces from Gaza and the release of a large number of Palestinian prisoners, including high-profile militants.
Izzat al-Rishq, a senior Hamas official, said the hostages would still be alive if Israel had accepted a US-backed cease-fire proposal that Hamas said it had agreed to in July.
Netanyahu has vowed to continue the fighting until Hamas is destroyed.
Top security officials say the intense pressure on Hamas has created favourable conditions for a cease-fire deal. The army, noting the difficulty of rescue operations, has acknowledged that a deal is the only way to bring home large numbers of hostages safely.
But critics have accused the prime minister of putting his personal interests over those of the hostages. The war's end likely will lead to an investigation into his government's failures in the October 7 attacks, the government's collapse and early elections.
Some analysts said the public outcry over the six hostages who died could signal a new level of political pressure on Netanyahu.
Goldberg-Polin's parents, US-born immigrants to Israel, became perhaps the most high-profile relatives of hostages on the international stage.
They met with US President Joe Biden and Pope Francis and on August 21, they addressed the Democratic National Convention.
Biden on Sunday said he was "devastated and outraged".
Some 250 hostages were taken on October 7. Israel now believes 101 remain in captivity, including 35 who are thought to be dead.
More than 100 were freed during a cease-fire in November in exchange for the release of Palestinians imprisoned by Israel.
Eight have been rescued by Israeli forces. Israeli troops mistakenly killed three Israelis who escaped captivity in December.
Hamas-led militants killed some 1200 people, mostly civilians, when they stormed into southern Israel on October 7.
Israel's retaliatory offensive in Gaza has killed over 40,000 Palestinians, according to local health officials, who do not say
with DPA
