Israel faced a wave of international condemnation Monday over a strike that Gaza officials said killed 45 people when it set off a fire that ripped through a tent city for displaced Palestinians.
Israel said it was looking into the "tragic accident" and its impact on civilians after the latest mass casualty event in the Gaza war, which has raged since October 7.
Adding to already heightened tensions since Israel launched a ground operation in the southern Gaza city of Rafah in early May, the Israeli and Egyptian militaries reported a "shooting incident" Monday that killed one Egyptian guard in the border area between Egypt and the southern Gaza Strip.
Both forces said they were investigating.
Israel's military said Sunday evening's attack in the southern Rafah area had targeted and killed two senior Hamas operatives -- but it also sparked a fire that Palestinians and many Arab countries condemned as a "massacre".
A US National Security Council spokesperson said Israel "must take every precaution possible to protect civilians".
The Israeli military said it was launching a probe.
"There is no safe place in Gaza. This horror must stop," UN Secretary General Antonio Guterres posted on social media, as diplomats said the UN Security Council will convene Tuesday in an emergency session to discuss the attack.
Displaced Gazan Khalil al-Bahtini was preparing to leave the impacted area, telling AFP Monday that "last night, the tent opposite to ours was targeted."
"We have loaded all our belongings, but we don't know where to go."
Israeli Prime Minister Benjamin Netanyahu said the government was investigating the "tragic accident" which he told parliament occurred "despite our best efforts" to protect civilians.
Relatives of captives held in Gaza, who have increased pressure on Netanyahu's government demanding action to secure a hostage release deal, heckled him from the public gallery as he was speaking, and raised posters of their loved ones.
Israel launched the attack on Rafah late Sunday, hours after Hamas unleashed a barrage of rockets at the Tel Aviv area, most of which were intercepted.
Israel's army said its aircraft "struck a Hamas compound in Rafah" and killed Yassin Rabia and Khaled Nagar, senior officials for the militant group in the occupied West Bank.
Gaza's civil defence agency said the strike ignited a fire that tore through a displacement centre in northwestern Rafah near a facility of the UN agency for Palestinian refugees, UNRWA.
"We saw charred bodies and dismembered limbs ... We also saw cases of amputations, wounded children, women and the elderly," said civil defence agency official Mohammad al-Mughayyir.
One survivor, a woman who declined to be named, said: "We heard a loud sound and there was fire all around us. The children were screaming."
Footage from the Palestinian Red Crescent Society showed chaotic nighttime scenes of paramedics racing to the attack site and evacuating the wounded.
Mughayyir said the rescue efforts were hampered by war damage and the impacts of Israel's siege, which has led to severe shortages of fuel and "water to extinguish fires".
The Israeli attack sparked strong protests from mediators Egypt and Qatar, as well as from other regional governments.
Egypt deplored the "targeting of defenceless civilians", calling it part of "a systematic policy aimed at widening the scope of death and destruction in the Gaza Strip to make it uninhabitable".
Jordan accused Israel of "ongoing war crimes", Saudi Arabia condemned "the continued massacres", and Turkish President Recep Tayyip Erdogan vowed "to hold these barbarians and murderers accountable".
Qatar condemned a "dangerous violation of international law" and voiced "concern that the bombing will complicate ongoing mediation efforts" towards a truce.
The African Union chair Moussa Faki Mahamat said on X that "Israel continues to violate international law... in contempt of an ICJ ruling two days ago ordering an end to its military action in Rafah."
The top world court, the International Court of Justice, on Friday ordered Israel to halt any offensive in Rafah and elsewhere that could bring about "the physical destruction" of the Palestinians.
The war started after the October 7 attack on southern Israel resulted in the deaths of more than 1,170 people, mostly civilians, according to an AFP tally based on Israeli official figures.
Militants also took 252 hostages, 121 of whom remain in Gaza, including 37 the army says are dead.
Israel's retaliatory offensive has killed at least 36,050 people in Gaza, mostly civilians, according to the Hamas-run territory's health ministry.
Philippe Lazzarini, head of UNRWA which has been central to aid operations in the besieged territory during the war, said on X that "with every day passing, providing assistance & protection becomes nearly impossible".
"The images from last night are testament to how Rafah has turned into hell on Earth," he said, citing "heavy movement restrictions", Israeli strikes and Hamas rocket launches, and other "challenges ... that do not allow us to distribute aid".
Dr Suhaib al-Hams, acting director at Rafah's Kuwait Speciality Hospital, said Monday it was now out of service and being evacuated after Israeli shelling hit the gate and "killed two medics".
On Tuesday, Spain, Ireland and Norway are due to formally recognise a Palestinian state -- a step so far taken by more than 140 UN members, but few western powers.
Israel opposes the move and on Monday announced punitive steps against Madrid, ordering its consulate in Jerusalem to stop offering services to Palestinians from June 1.
