Israel's military said its troops came under fire from Hamas militants in southern Gaza
The official spoke on condition of anonymity pending a formal announcement on the halt in aid, a little over a week since the start of the US-proposed ceasefire aimed at ending two years of war.
Israel's military earlier Sunday said its troops came under fire from Hamas militants in southern Gaza, and later said two soldiers were killed there.
Israel's military said then it struck dozens of what it called Hamas targets. Health officials said at least 29 Palestinians were killed across Gaza, including children.
A senior Egyptian official involved in the ceasefire negotiations said "round-the-clock" contacts were underway to deescalate the situation. The official spoke on condition of anonymity because he wasn't authorized to speak to reporters.
There was no immediate US comment.
Israeli Prime Minister Benjamin Netanyahu directed the military to take "strong action" against any ceasefire violations but didn't threaten to return to war.
Israel's military said militants had fired at troops in areas of Rafah city that are Israeli-controlled according to agreed-upon ceasefire lines.
Hamas, which continued to accuse Israel of multiple ceasefire violations, said communication with its remaining units in Rafah had been cut off for months and "we are not responsible for any incidents occurring in those areas."
Palestinians quickly feared the return of war.
"It will be a nightmare," said Mahmoud Hashim, a father of five from Gaza City, who appealed to US President Donald Trump and other mediators to prevent the ceasefire's collapse.
An Israeli airstrike on a makeshift coffeehouse in Zawaida town in central Gaza killed at least six Palestinians, according to Gaza's Health Ministry, part of the Hamas-run government.
Another strike killed at least two people near the Al-Ahly soccer club in the Nuseirat refugee camp, the ministry said. The strike hit a tent and wounded eight others, said Al-Awda Hospital, which received the casualties.
The hospital said it also received the bodies of four people killed in a strike on a school sheltering displaced families in Nuseirat. Six others were killed in a tent in Nuseirat, one killed at a charging point west of Nuseirat and four killed at a house in Bureij camp.
Another strike hit a tent in the Muwasi area of Khan Younis in the south, killing at least four people, including a woman and two children, according to Nasser Hospital.
A strike in Beit Lahiya in the north killed two men, according to Shifa hospital.
Israel identified the remains of two hostages released by Hamas overnight.
Netanyahu's office said the bodies belonged to Ronen Engel, a father from Kibbutz Nir Oz, and Sonthaya Oakkharasri, a Thai agricultural worker from Kibbutz Be'eri.
Both were believed to have been killed during the Hamas-led attack on southern Israel on Oct. 7, 2023, which sparked the war. Engel's wife, Karina, and two of his three children were kidnapped and released in a ceasefire in November 2023.
Hamas in the past week has handed over the remains of 12 hostages.
Hamas' armed wing, the Qassam Brigades, said that it found the body of a hostage and would return it on Sunday "if circumstances in the field" allowed. It warned that any escalation by Israel would hamper search efforts.
Israel on Saturday pressed Hamas to fulfill its ceasefire role of returning the remains of all 28 deceased hostages, saying the Rafah border crossing between Gaza and Egypt would stay closed "until further notice."
Hamas says the war's devastation and Israeli military control of certain areas of Gaza have slowed the handover. Israel believes Hamas has access to more bodies than it has returned.
Israel has released 150 bodies of Palestinians back to Gaza, including 15 on Sunday, according to Gaza's Health Ministry. Israel has neither identified the bodies nor said how they died. The ministry posts photos of bodies on its website to help families attempting to locate loved ones. Some are decomposed and blackened. Some are missing limbs and teeth.
Only 25 bodies have been identified, the Health Ministry said.
Israel and Hamas earlier exchanged 20 living hostages for more than 1,900 Palestinian prisoners and detainees.
A Hamas delegation led by chief negotiator Khalil al-Hayya arrived in Cairo to follow up the implementation of the ceasefire deal with mediators and other Palestinian groups, Hamas said in a statement.
The next stages are expected to focus on disarming Hamas, Israeli withdrawal from additional areas it controls in Gaza, and future governance of the devastated territory.
Hamas spokesman Hazem Kassem said late Saturday that the second phase of negotiations "requires national consensus." He said Hamas has begun discussions to "solidify its positions."
The US plan proposes the establishment of an internationally backed authority to run Gaza.
Kassem reiterated that Hamas won't be part of the ruling authority in a postwar Gaza. He called for the prompt establishment of a body of Palestinian technocrats to run day-to-day affairs.
For now, "government agencies in Gaza continue to perform their duties, as the (power) vacuum is very dangerous," he said.
The Rafah crossing was the only one not controlled by Israel before the war. It has been closed since May 2024, when Israel took control of the Gaza side.
A fully reopened crossing would make it easier for Palestinians to seek medical treatment, travel or visit family in Egypt, home to tens of thousands of Palestinians.
On Sunday, the Palestinian Authority's Interior Ministry in Ramallah announced procedures for Palestinians wishing to leave or enter Gaza through the Rafah crossing. For those who want to leave, Palestinian Embassy staff from Cairo will be at the crossing to issue temporary travel documents for entry into Egypt. Palestinians who wish to enter Gaza will need to apply at the embassy.
The Israel-Hamas war has killed more than 68,000 Palestinians, according to Gaza's Health Ministry, which doesn't distinguish between civilians and combatants in its count. The ministry maintains detailed casualty records that are seen as generally reliable by U.N. agencies and independent experts. Israel has disputed them without providing its own toll.
Thousands more people are missing, according to the Red Cross.
Hamas-led militants killed around 1,200 people, mostly civilians, and abducted 251 people in the attack that sparked the war.
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