Israeli PM says airstrikes across Gaza that killed at least 413 are 'only the beginning'

The surprise bombardment shattered a ceasefire in place since January and threatened to fully reignite the 17-month-old war.

Israel launched airstrikes across the Gaza Strip early on Tuesday, killing more than 400 Palestinians, local health officials said, and shattering a ceasefire in place since January with its deadliest bombardment in a 17-month war with Hamas.

Prime Minister Benjamin Netanyahu ordered the strikes, which killed mostly women and children, after Hamas refused Israeli demands to change the ceasefire agreement.

Officials said the operation was open-ended and expected to expand. The White House said it had been consulted and voiced support for Israel's actions.

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Netanyahu said late on Tuesday (Wednesday AEDT) the airstrikes were "only the beginning" and a "necessary condition for freeing hostages."

He described Israel's renewed deadly attacks on Gaza as a "return to battle forcefully," arguing that military pressure is necessary to get the remaining hostages released. The Israeli military would continue fighting Hamas with increasing force, he added.

Netanyahu said negotiations from now on will be "under fire."

The Israeli military ordered people to evacuate eastern Gaza and head toward the centre of the territory, indicating that Israel could soon launch renewed ground operations.

The new campaign comes as aid groups warn supplies are running out two weeks after Israel cut off all food, medicine, fuel and other goods to Gaza's 2 million Palestinians.

"Israel will, from now on, act against Hamas with increasing military strength," Netanyahu's office said.

The attack during the Muslim holy month of Ramadan could resume a war that has already killed tens of thousands of Palestinians and caused widespread destruction across Gaza. It also raised questions about the fate of the roughly two dozen Israeli hostages held by Hamas who are believed to still be alive.

A senior Hamas official said Netanyahu's decision to return to war amounts to a "death sentence" for the remaining hostages. Izzat al-Risheq accused Netanyahu of launching the strikes to try and save his far-right governing coalition and called on mediators to "reveal facts" on who broke the truce. Hamas said at least four senior officials were killed in Tuesday's strikes.

There were no reports of any attacks by Hamas several hours after the bombardment, indicating it still hoped to restore the truce.

The strikes came as Netanyahu comes under mounting domestic pressure, with mass protests planned over his handling of the hostage crisis and his decision to fire the head of Israel's internal security agency. His latest testimony in a long-running corruption trial was cancelled after the strikes.

Regional leaders denounce Israel

Turkish President Recep Tayyip Erdogan branded Israel as a "terrorist state" feeding on the "blood, lives and tears of innocent" people.

A vocal critic of Israel's actions in Gaza, Erdogan on Tuesday accused Israel of committing "genocide" in Gaza. He pledged to increase diplomatic efforts to stop the violence and ensure a ceasefire.

Iran's Foreign Ministry said in a statement that letting Israel resume its deadly strikes and block all aid to Gaza "poses catastrophic consequences for global peace and security."

Some advocacy groups and other rights experts have accused Israel of genocide against Palestinians in Gaza — charges Israel vehemently denies.

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The main group representing families of the captives accused the government of backing out of the ceasefire, saying it "chose to give up on the hostages".

"We are shocked, angry and terrified by the deliberate dismantling of the process to return our loved ones from the terrible captivity of Hamas," the Hostages and Missing Families Forum said in a statement.

Wounded stream into Gaza hospitals

A strike on a home in the southern city of Rafah killed 17 members of one family, including at least 12 women and children, according to the European Hospital, which received the bodies. The dead included five children, their parents, and another father and his three children.

In the southern city of Khan Younis, Associated Press reporters saw explosions and plumes of smoke. Ambulances brought wounded people to Nasser Hospital, where patients lay on the floor, some screaming. A young girl cried as her bloody arm was bandaged.

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Many Palestinians said they had expected a return to war when talks over the second phase of the ceasefire did not begin as scheduled in early February. Israel instead embraced an alternative proposal and cut off all shipments of food, fuel and other aid to the territory's 2 million Palestinians to try to pressure Hamas to accept it.

"Nobody wants to fight," Palestinian resident Nidal Alzaanin told the AP by phone from Gaza City.

"Everyone is still suffering from the previous months."

Gaza's Health Ministry said at least 413 people were killed in the strikes and hundreds more wounded. Rescuers were still searching the rubble for dead and wounded as the strikes continued. It was among the deadliest days of the war.

US backs Israel and blames Hamas

The White House sought to blame Hamas for the renewed fighting. National Security Council spokesman Brian Hughes said the militant group "could have released hostages to extend the ceasefire but instead chose refusal and war".

An Israeli official, speaking on condition of anonymity to discuss the unfolding operation, said Israel was striking Hamas' military, leaders and infrastructure and planned to expand the operation beyond air attacks.

The official accused Hamas of attempting to rebuild and plan new attacks. Hamas militants and security forces quickly returned to the streets in recent weeks after the ceasefire went into effect.

Netanyahu's office said the Israeli leader held security consultations with senior officials. It did not provide further details.

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Talks on a second phase of the ceasefire had stalled

The strikes came two months after a ceasefire was reached to pause the war. Over six weeks, Hamas released 25 Israeli hostages and the bodies of eight more in exchange for nearly 2000 Palestinian prisoners in a first phase of the ceasefire.

But since that ceasefire ended two weeks ago, the sides have not been able to agree on a way forward with a second phase aimed at releasing the 59 remaining hostages, 35 of whom are believed to be dead, and ending the war altogether.

Hamas has demanded an end to the war and full withdrawal of Israeli troops in exchange for the release of the remaining hostages. Israel says it will not end the war until it destroys Hamas' governing and military capabilities and frees all hostages — two goals that could be incompatible.

Netanyahu's office on Tuesday said Hamas had "repeatedly refused to release our hostages and rejected all offers it received from the US presidential envoy, Steve Witkoff, and from the mediators".

Israel wants Hamas to release half of the remaining hostages in return for a promise to negotiate a lasting truce.

Hamas instead wants to follow the ceasefire deal reached by the two sides, which calls for negotiations to begin on the ceasefire's more difficult second phase, in which the remaining hostages would be released and Israeli forces would withdraw from Gaza.

A return to war would allow Netanyahu to avoid the tough trade-offs called for in the second phase of the agreement and the thorny question of who would govern Gaza.

It would also shore up his coalition, which depends on far-right lawmakers who want to depopulate Gaza and re-build Jewish settlements there.

Gaza already was in a humanitarian crisis

The war erupted when Hamas-led militants stormed into southern Israel on October 7, 2023, killing some 1200 people, mostly civilians, and taking 251 hostages. Most have been released in ceasefires or other deals, with Israeli forces rescuing only eight and recovering dozens of bodies.

Israel responded with a military offensive that killed more than 48,000 Palestinians, according to local health officials, and displaced an estimated 90 per cent of Gaza's population. The territory's Health Ministry doesn't differentiate between civilians and militants, but says more than half of the dead have been women and children.

The ceasefire had brought some relief to Gaza and allowed hundreds of thousands of displaced Palestinians to resume to what remained of their homes.

Netanyahu faces mounting criticism

The released hostages, some of whom were emaciated, have repeatedly implored the government to press ahead with the ceasefire to return all remaining captives. Tens of thousands of Israelis have taken part in mass demonstrations calling for a ceasefire and return of all hostages.

Mass demonstrations are planned later on Tuesday and Wednesday following Netanyahu's announcement this week that he wants to fire the head of Israel's Shin Bet internal security agency.

Critics have lambasted the move as an attempt by Netanyahu to divert blame for his government's failures in the October 7 attack and handling of the war.

Since the ceasefire in Gaza began in mid-January, Israeli forces have killed dozens of Palestinians who the military says approached its troops or entered unauthorised areas.

Still, the deal has tenuously held without an outbreak of wide violence. Egypt, Qatar and the United States have been trying to mediate the next steps in the ceasefire.

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