Israeli fire killed at least three Palestinians and wounded dozens of others near an aid distribution site operated by the US-based Gaza Humanitarian Foundation, local health authorities said on Monday.
The Israeli military said it was aware of reports of casualties and the incident was being thoroughly looked into.
It said in a statement that troops operating overnight in Rafah, which is under full Israeli military control, in the southern Gaza Strip, had fired warning shots "to prevent several suspects approaching them", adding the incident took place about a 1 km away from the aid distribution site.
The GHF, a private group sponsored by the United States and endorsed by Israel, said there had been no fatalities or injuries at its distribution site or the surrounding area.
Reuters could not independently verify what took place.
The reported incident was the latest in a series underscoring the volatile security situation that has complicated aid delivery to Gaza, following the easing last month of an almost three-month Israeli blockade.
On Sunday, Palestinian and international officials said at least 31 people were killed and dozens wounded near the same site, one of several operated by the Gaza Humanitarian Foundation in Rafah.
The Israeli military denied firing at people gathering to collect aid, and the GHF said Sunday's distribution was carried out without incident, describing reports of deaths as fabricated by Hamas.
In an update earlier on Monday, the GHF said it has distributed the load of 21 trucks to Palestinians. It added that Monday's deliveries raised the number of meals it has distributed since it began operations to nearly 6 million.
The United Nations has said most of Gaza's 2 million population is at risk of famine after an 11-week Israeli blockade on aid entering the strip.
The Gaza Humanitarian Foundation launched its first distribution sites last week and said it would launch more. The Israeli military has said GHF had established four sites so far.
Its aid plan, which bypasses traditional aid groups, has come under fierce criticism from the United Nations and humanitarian organizations, which say the GHF does not follow humanitarian principles.
On Monday, the Palestinian NGOs Network urged a boycott of what it called the "US-Israeli aid mechanism" in protest over the killings on Sunday.
It said that the new mechanism has deepened the humanitarian crisis in Gaza and aimed to "bolster the occupation's security and political goals" in pushing Palestinians out of northern Gaza towards the south.
CEASEFIRE TALKS TO RESUME
Israel and Hamas, meanwhile, traded blame for the faltering of a new Arab and US mediation bid to secure a temporary ceasefire and the release of Israeli hostages held in Gaza by Hamas, in exchange for Palestinians in Israeli jails.
Hamas said on Saturday it was seeking amendments to a US-backed ceasefire proposal, but US President Donald Trump's envoy, Steve Witkoff, rejected the group's response as "totally unacceptable".
Egypt and Qatar said in a joint statement that they were continuing efforts to overcome disagreements and reach a ceasefire.
Hamas on Sunday welcomed those efforts and expressed its readiness to start a round of indirect negotiations immediately.
On Monday, a Palestinian official close to the mediation effort said Hamas leaders were in constant contact with Egyptian and Qatari mediators in Cairo and Doha, hoping they could pressure Israel to agree to holding talks on ending the war in Gaza as part of the ceasefire deal.
Israel says it accepts a temporary truce to release hostages, but that war can only end once Hamas is driven out of Gaza.
Israel began its offensive in Gaza in response to the Hamas-led attack on southern Israel on October 7, 2023, which killed 1,200 people, mostly civilians, according to Israeli tallies, and saw 251 taken as hostages into Gaza.
Israel's campaign has devastated much of Gaza, killing more than 54,000 Palestinians and destroying most buildings. Much of the population now lives in shelters in makeshift camps.