JERUSALEM >> Israeli forces launched deadly aerial attacks across the Gaza Strip on Tuesday, ending a temporary ceasefire with Hamas that began in January, and raising the prospect of a return to all-out war.

More than 400 people, including children, were killed in the strikes, Gaza’s Health Ministry said. Those numbers did not distinguish between civilians and combatants — but the relentless Israeli bombardment produced one of the war’s deadliest single-day tolls.

The attacks came after weeks of fruitless negotiations aimed at extending the fragile ceasefire, which paused 15 months of devastating fighting in the territory. The truce’s first phase expired in early March, but it had largely held as diplomats worked to broker an extension to free the surviving Israeli hostages and end the war.

The office of Israeli Prime Minister Benjamin Netanyahu said he had ordered the military operation after Hamas’ “repeated refusal” to release the remaining captives seized in the Oct. 7, 2023, assault on Israel and the bodies of those hostages who have died. Of the 59 remaining in Gaza, fewer than half are believed to be alive.

In an address later Tuesday, Netanyahu suggested that more Israeli attacks in Gaza were coming and would be carried out in tandem with negotiations with Hamas.

“This is just the beginning,” he said. “We will keep fighting to achieve all of the war’s objectives.”

Hamas officials argued that Israel had brazenly overturned the truce, but did not immediately respond militarily to the strikes. It was unclear whether the Palestinian armed group — badly weakened after more than a year of war — would strike back or head to the negotiating table.

In Israel, relatives of the hostages said the renewed Israeli attacks had heightened their fears that the remaining captives might never return alive. They accused Netanyahu and his government of abandoning the hostages, and some gathered in rallies demanding an immediate deal with Hamas to secure their freedom.

The Trump administration — which has been seeking to broker a deal between Israel and Hamas — appeared to back Israel’s decision to resume wide-scale attacks in Gaza. White House press secretary Karoline Leavitt said Israel had consulted with the United States before launching its assault.

The Israeli airstrikes in Gaza began slightly before 2:30 a.m. local time. Their ferocity recalled the war’s earliest days, when Israel launched heavy attacks in the enclave.