The Israeli military said on Sunday a ceasefire in Gaza had resumed after an attack killed two of its soldiers and prompted a wave of airstrikes that Palestinians said killed 26 people, in the most serious test yet of this month's truce.

US President Donald Trump said the ceasefire he brokered was still in place. Hamas leadership, he said, may not be involved in the violations.

"We think maybe the leadership isn't involved in that," he told reporters aboard Air Force One.

"Either way ... it's going to be handled toughly but properly."

Trump said he did not know whether the Israeli strikes were justified. "I'd have to get back to you on that," he said.

Aid into Gaza was set to resume on Monday following US pressure, an Israeli security source said, shortly after Israel announced a halt in supplies in response to what it said was a "blatant" violation by Hamas of the truce.

The Israeli military said it struck Hamas targets across the enclave, including field commanders, gunmen, a tunnel and weapons depots, after militants launched an anti-tank missile and fired on its troops, killing the soldiers.

The strikes killed at least 26 people, including at least one woman and one child, according to local residents and health authorities.

At least one strike hit a former school sheltering displaced people in the area of Nuseirat, residents said.

"We're going to have to see what's happening. We want to make sure that it's going to be very peaceful with Hamas," Trump said.

Trump's envoy Steve Witkoff and son-in-law Jared Kushner were expected to travel to Israel on Monday, an Israeli official and a US official said.

The armed wing of Hamas said it remained committed to the ceasefire agreement, was unaware of clashes in Rafah, and had not been in contact with groups there since March.

US Vice President JD Vance did not mention the Israeli strikes when speaking to reporters, but said there were about 40 different cells of Hamas and no security infrastructure yet in place to confirm their disarmament.

"Some of those cells will probably honor the ceasefire. Many of those cells, as we saw some evidence of today, will not," he said.

"Before we actually can ensure that Hamas is properly disarmed, that's going to require ... some of these Gulf Arab states, to get forces in there, to actually apply some law and order and security keeping on the ground."

Israeli Prime Minister Benjamin Netanyahu said he had ordered the military to respond forcefully to what he described as Hamas' violations of the ceasefire.

PATH TO PEACE IS UNCERTAIN

Israeli soldiers stand next to tanks near the Israel-Gaza border, in Israel, October 19, 2025.

Fearing the truce may collapse, some Palestinians rushed to buy goods from a main market in Nuseirat and families fled their homes in Khan Younis further south, after airstrikes hit nearby.

The strikes were reminiscent of Israel's response to what it viewed as serious violations of its ceasefire with Hamas' Lebanese ally Hezbollah in late 2024, less than a week after it came into effect and after days of mutual accusations of truce breaches, though that ceasefire has since largely held.

But formidable obstacles remain in the way of a durable peace in Gaza, where a ceasefire collapsed in March after nearly two months of relative calm when Israel unleashed a barrage of airstrikes.

DISPUTE OVER BODIES OF DECEASED HOSTAGES

The new ceasefire took effect on October 10, halting two years of war, but the Israeli government and Hamas have been accusing each other of violations of the ceasefire for days.

Israeli Defense Minister Israel Katz said the "yellow line" to where Israeli forces had pulled back under the ceasefire deal would be physically marked and that any violation of the ceasefire or attempt to cross the line would be met with fire.

Hamas detailed what it said was a series of violations by Israel that it says have left 46 people dead and stopped essential supplies from reaching the enclave.

On Saturday, Israel said the Rafah border crossing between Gaza and Egypt, which had been expected to be reopened this week, would remain closed and that its reopening would depend on Hamas fulfilling its obligations under the ceasefire.

Israel says Hamas is being too slow in handing over bodies of deceased hostages. Hamas last week released all 20 living hostages it had been holding and in the following days has handed over 12 of the 28 deceased captives.

MORE AID IS NEEDED

Hamas says it has no interest in keeping the bodies of remaining hostages and that special equipment is needed to recover corpses buried under rubble.

The Rafah crossing has largely been shut since May 2024. The ceasefire deal also includes the ramping up of aid to Gaza, where hundreds of thousands of people were determined in August to be affected by famine, according to the IPC global hunger monitor.

The crossing has in previous ceasefires functioned as a key conduit for humanitarian aid to flow into the enclave.

Although the flow of aid through another crossing had, until Sunday's decision to halt aid, increased significantly since the ceasefire began, the United Nations says far more is needed.

Key questions of Hamas disarming, future governance of Gaza, the make-up of an international "stabilization force", and moves towards creation of a Palestinian state have yet to be resolved.